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1.
Oxid Med Cell Longev ; 2020: 4960507, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33082909

RESUMEN

Salinity is a worldwide, threatening problem affecting socioeconomic status globally. Saline land comprises salt content in soil, plants, and drinking water. Livestock farming is the worthy option for proper utilization of saline land in a cost-effective approach. Animals reared on this land experience a variety of stresses. Such stresses promote oxidative stress and reduced animal performance. The purpose of this study was to investigate the antioxidative function of vitamin E and selenium (Se) on pregnant/nonpregnant animals reared on the saline environment. A total of 36 multiparous pregnant (n = 18) and nonpregnant (n = 18) goats weighing about 38-45 (average 41.5) kg were equally divided into control and supplemented groups. The experiment lasted from 120 days of gestation to 15 days after parturition for pregnant goats and 0 to 45 days for nonpregnant cyclic goats (>50 days post-kidding). The supplemented group was administered vitamin E (1000 mg/kg BW) and selenium (3 mg/50 kg BW), while the control group was kept on normal saline (0.9% NaCl) with the same route 15 days apart. The blood samples were collected with 15 days apart during the entire experimental period of 45 days and subjected to assessment of enzymatic/nonenzymatic antioxidants, hydrolytic enzymes, oxidants, stress metabolic biomarkers, Se, and progesterone concentration of (pregnant) animals. Results revealed that vitamin E and Se supplementation significantly enhanced the activity of enzymatic (catalase and peroxidase) and nonenzymatic antioxidants such as total phenolic/flavonoid content and vitamin C and increased blood plasma level of Se concentration in comparison with the control group (P < 0.01). Exposure to antioxidant supplementation mitigated lipid peroxidation and enhanced progesterone level and total antioxidant capacity (P < 0.01) as compared to the control group in pregnant goats. Administration of vitamin E and selenium promoted kid survival rate (100%) along with increased initial birth weight, daily average weight gain, and total weight gain in comparison with the control group. Besides, the twinning rate and sex ratio were also recorded in pregnant animals. It is concluded that vitamin E and Se supplementation ameliorated salinity-induced oxidative stress, improved antioxidant status, and enhanced reproductive and growth performance of suckling kids reared on saline land.


Asunto(s)
Antioxidantes/metabolismo , Estrés Oxidativo/efectos de los fármacos , Selenio/farmacología , Vitamina E/farmacología , Animales , Ácido Ascórbico/sangre , Esterasas/sangre , Femenino , Flavonoides/sangre , Cabras , Masculino , Fenol/sangre , Embarazo , Progesterona/sangre , Solución Salina/farmacología , Selenio/sangre , Suelo/química , Superóxido Dismutasa/metabolismo , Regulación hacia Arriba/efectos de los fármacos
2.
J Mycol Med ; 28(1): 15-22, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29551442

RESUMEN

Isavuconazole, the active moiety of its prodrug isavuconazonium, is a new extended-spectrum triazole whose activity against yeasts, molds, including Aspergillus and mucorales, and dimorphic fungi has been shown in vitro and in preclinical models. The most relevant pharmacokinetics features are water-solubility of the prodrug, rapid cleavage of the prodrug into active moiety and cleavage product by plasmatic esterases, high oral bioavailability of isavuconazole with an extensive penetration into most tissues and a good safety profile even in case of renal impairment. The results of two main clinical studies have led to an approval by FDA and EMA in the treatment of invasive aspergillosis and invasive mucormycosis. Isavuconazole is non-inferior to voriconazole in terms of response and survival in invasive aspergillosis and has shown improved safety and tolerability. Importantly, less hepatobiliary, skin and eye disorders have been reported in isavuconazole-treated patients. Isavuconazole has therefore been granted a grade A-I recommendation by the European Conference on Infections in Leukemia (ECIL) for the treatment of invasive aspergillosis. Efficacy has also been demonstrated in mucormycosis in an open-label study. Survival was similar to the survival of matched patients from the international Fungiscope registry and treated with an amphotericin B formulation. Isavuconazole failed to show non-inferiority to caspofungin in a large double-blind candidemia trial. The aim of this review is to give the reader an overview of the data available so far to support inclusion of isavuconazole in the anti-mold therapeutic arsenal.


Asunto(s)
Antifúngicos/farmacocinética , Azoles/farmacocinética , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Nitrilos/farmacocinética , Piridinas/farmacocinética , Triazoles/farmacocinética , Animales , Antifúngicos/efectos adversos , Antifúngicos/metabolismo , Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Azoles/efectos adversos , Azoles/metabolismo , Azoles/uso terapéutico , Candidemia/tratamiento farmacológico , Ensayos Clínicos como Asunto , Método Doble Ciego , Evaluación Preclínica de Medicamentos , Esterasas/sangre , Humanos , Ratones , Mucormicosis/tratamiento farmacológico , Nitrilos/efectos adversos , Nitrilos/metabolismo , Nitrilos/uso terapéutico , Piridinas/efectos adversos , Piridinas/metabolismo , Piridinas/uso terapéutico , Triazoles/efectos adversos , Triazoles/metabolismo , Triazoles/uso terapéutico
3.
Neurotoxicology ; 45: 22-30, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25196089

RESUMEN

Chlorpyrifos (CPF) is an organophosphorus cholinesterase inhibitor widely used as an insecticide. Neuro and genotoxicity of this agent were evaluated following daily subcutaneous injections at 0.1, 1 and 10mg/kg or its vehicle to laboratory rats during one week, at the end of which somatosensory evoked potentials (SEP) and power spectrum of the electroencephalogram (EEGp) were recorded under urethane anesthesia. In another group of conscious animals, auditory startle reflex (ASR) was evaluated followed, after euthanasia, with measurements of plasma B-esterases, and genotoxicity with the alkaline comet assay (ACA) at the same CPF doses. The results indicated a CPF dose related inhibition of B-esterases. Enhanced inhibition of the ASR by a subthreshold pre-pulse was observed at all doses and ACA showed a significant higher DNA damage than vehicle controls in animals exposed to 10mg/kg CPF. A trend to higher frequencies of EEGp and an increase in amplitude of the first negative wave of the SEP were found at all doses. The first positive wave of the SEP decreased at the CPF dose of 10mg/kg. In summary, a shift to higher EEG frequencies and alterations of somatosensory and auditory input to the central nervous system were sensitive manifestations of CPF toxicity, associated with depression of B-esterases. The changes in electrical activity of the cerebral cortex and DNA damage observed at doses that do not elicit overt toxicity may be useful in the detection of CPF exposure before clinical signs appear.


Asunto(s)
Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiopatología , Cloropirifos/toxicidad , Inhibidores de la Colinesterasa/toxicidad , Daño del ADN/efectos de los fármacos , Reflejo de Sobresalto/efectos de los fármacos , Acetilcolinesterasa/sangre , Estimulación Acústica , Animales , Temperatura Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Butirilcolinesterasa/sangre , Carboxilesterasa/sangre , Relación Dosis-Respuesta a Droga , Electroencefalografía , Esterasas/sangre , Esterasas/efectos de los fármacos , Potenciales Evocados Somatosensoriales/efectos de los fármacos , Masculino , Pruebas de Mutagenicidad , Inhibición Prepulso/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Ratas Wistar
4.
J Med Chem ; 52(21): 6790-802, 2009 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-19821586

RESUMEN

Hydroxamates are valuable tools for chemical biology as well as interesting leads for medicinal chemistry. Although many hydroxamates display nanomolar activities against metalloproteases, only three hydroxamates have reached the market, among which is the HDAC inhibitor vorinostat. Failures in development are generally attributed to lack of selectivity, toxicity, or poor stability. To help medicinal chemists with respect to plasma stability, we have performed the first and preliminary study on structure-plasma stability for hydroxamates. We define some structural rules to predict or improve the plasma stability in the preclinical stage.


Asunto(s)
Ácidos Hidroxámicos/síntesis química , Animales , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Esterasas/sangre , Semivida , Humanos , Hidrólisis , Interacciones Hidrofóbicas e Hidrofílicas , Ácidos Hidroxámicos/sangre , Ácidos Hidroxámicos/química , Plasma , Profármacos/síntesis química , Profármacos/química , Profármacos/metabolismo , Ratas , Ratas Sprague-Dawley , Estereoisomerismo , Relación Estructura-Actividad
6.
Toxicol Appl Pharmacol ; 212(2): 156-66, 2006 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-16169030

RESUMEN

Deltamethrin, a widely used type II pyrethroid insecticide, is a relatively potent neurotoxicant. While the toxicity has been extensively examined, toxicokinetic studies of deltamethrin and most other pyrethroids are very limited. The aims of this study were to identify, characterize, and assess the relative contributions of esterases and cytochrome P450s (CYP450s) responsible for deltamethrin metabolism by measuring deltamethrin disappearance following incubation of various concentrations (2 to 400 microM) in plasma (esterases) and liver microsomes (esterases and CYP450s) prepared from adult male rats. While the carboxylesterase metabolism in plasma and liver was characterized using an inhibitor, tetra isopropyl pyrophosphoramide (isoOMPA), CYP450 metabolism was characterized using the cofactor, NADPH. Michaelis-Menten rate constants were calculated using linear and nonlinear regression as applicable. The metabolic efficiency of these pathways was estimated by calculating intrinsic clearance (Vmax/Km). In plasma, isoOMPA completely inhibited deltamethrin biotransformation at concentrations (2 and 20 microM of deltamethrin) that are 2- to 10-fold higher than previously reported peak blood levels in deltamethrin-poisoned rats. For carboxylesterase-mediated deltamethrin metabolism in plasma, Vmax=325.3+/-53.4 nmol/h/ml and Km=165.4+/-41.9 microM. Calcium chelation by EGTA did not inhibit deltamethrin metabolism in plasma or liver microsomes, indicating that A-esterases do not metabolize deltamethrin. In liver microsomes, esterase-mediated deltamethrin metabolism was completely inhibited by isoOMPA, confirming the role of carboxylesterases. The rate constants for liver carboxylesterases were Vmax=1981.8+/-132.3 nmol/h/g liver and Km=172.5+/-22.5 microM. Liver microsomal CYP450-mediated biotransformation of deltamethrin was a higher capacity (Vmax=2611.3+/-134.1 nmol/h/g liver) and higher affinity (Km=74.9+/-5.9 microM) process than carboxylesterase (plasma or liver) detoxification. Genetically engineered individual rat CYP450s (Supersomes) were used to identify specific CYP450 isozyme(s) involved in the deltamethrin metabolism. CYP1A2, CYP1A1, and CYP2C11 in decreasing order of importance quantitatively, metabolized deltamethrin. Intrinsic clearance by liver CYP450s (35.5) was more efficient than that by liver (12.0) or plasma carboxylesterases (2.4).


Asunto(s)
Insecticidas/metabolismo , Microsomas Hepáticos/metabolismo , Nitrilos/metabolismo , Piretrinas/metabolismo , Animales , Butirilcolinesterasa/metabolismo , Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Hidrolasas de Éster Carboxílico/metabolismo , Cromatografía Líquida de Alta Presión , Sistema Enzimático del Citocromo P-450/sangre , Sistema Enzimático del Citocromo P-450/metabolismo , ADN Complementario/biosíntesis , ADN Complementario/genética , Esterasas/sangre , Esterasas/metabolismo , Técnicas In Vitro , Insecticidas/sangre , Insecticidas/farmacocinética , Masculino , Nitrilos/sangre , Nitrilos/farmacocinética , Piretrinas/sangre , Piretrinas/farmacocinética , Ratas , Ratas Sprague-Dawley
7.
J Radiat Res ; 45(1): 133-9, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15133301

RESUMEN

The radioprotective effect of an extract of the plant Phyllanthus amarus (P. amarus) was investigated in adult BALB/c mice. P. amarus extract (750 mg/kg b.wt and 250 mg/kg b.wt) was administered orally to mice for five days prior to whole body radiation (6 Gy) and for one month after radiation. The animals were sacrificed on days 3, 9, 12, and 30 after radiation. P. amarus significantly increased the total W.B.C count, bone marrow cellularity, and alpha-esterase activity as compared to untreated radiation-exposed animals. P. amarus treatment also increased the activity of various antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione peroxidase (GPX), and glutathione reductase (GR), both in blood and tissue, which were reduced by radiation treatment. There was also a significant increase in the glutathione (GSH) levels of blood and tissue. Lipid peroxidation levels, which were increased after radiation, were significantly reduced by P. amarus treatment, both in serum and liver. The results collectively indicate that P. amarus extract could increase the antioxidant defense mechanism in mice and there by protect the animals from radiation-induced cellular damage.


Asunto(s)
Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/efectos de la radiación , Phyllanthus/metabolismo , Extractos Vegetales/administración & dosificación , Traumatismos Experimentales por Radiación/prevención & control , Protectores contra Radiación/administración & dosificación , Administración Oral , Animales , Células 3T3 BALB , Proteínas Sanguíneas/análisis , Células de la Médula Ósea/patología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Esterasas/sangre , Femenino , Recuento de Leucocitos , Ratones , Fitoterapia/métodos , Componentes Aéreos de las Plantas/metabolismo , Traumatismos Experimentales por Radiación/patología , Tolerancia a Radiación/efectos de los fármacos , Irradiación Corporal Total
8.
Arterioscler Thromb Vasc Biol ; 23(1): 104-10, 2003 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-12524232

RESUMEN

OBJECTIVE: The role of insulin in atherosclerosis progression in diabetes is uncertain. We examined the effects of oral insulin supplementation on atherogenesis in apolipoprotein E-deficient (E(0)) mice. METHODS AND RESULTS: One-month-old male E(0) mice were orally supplemented with human insulin (0.1, 0.5, and 1 U/mL) or placebo for 3 months. At the end of the study, serum and macrophage oxidative stress and atherosclerosis progression were studied. Insulin reduced lesion size by 22% to 37% (P<0.05) in all study groups. Lipid peroxides serum levels were 18% lower (P<0.01), and serum paraoxonase activity was 30% higher (P<0.01) in mice supplemented with 1.0 U/mL insulin compared with controls. Insulin reduced mouse peritoneal macrophage (MPM) lipid peroxides content and superoxide anion release by up to 44% and 62%, respectively (P<0.01). In addition, oral insulin reduced MPM cholesterol content and cholesterol biosynthesis by up to 36% and 53%, respectively (P<0.01). In vitro incubation of E(0) mice MPM with increasing insulin concentrations (0 to 100 micro U/mL) resulted in a dose-dependent reduction of cholesterol synthesis by up to 66% (P<0.05). CONCLUSIONS: In E(0) mice, oral insulin supplementation attenuates the atherosclerotic process. This may be attributable to insulin-mediated reduction of oxidative stress in serum and macrophages as well as reduction in macrophage cholesterol content.


Asunto(s)
Apolipoproteínas E/deficiencia , Arteriosclerosis/tratamiento farmacológico , Arteriosclerosis/genética , Insulina/uso terapéutico , Administración Oral , Animales , Aorta/efectos de los fármacos , Aorta/patología , Enfermedades de la Aorta/sangre , Enfermedades de la Aorta/tratamiento farmacológico , Apolipoproteínas E/genética , Arteriosclerosis/sangre , Arildialquilfosfatasa , Glucemia/metabolismo , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Colesterol/biosíntesis , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Esterasas/sangre , Humanos , Insulina/administración & dosificación , Insulina/sangre , Peroxidación de Lípido/efectos de los fármacos , Lípidos/sangre , Macrófagos Peritoneales/química , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/metabolismo , Masculino , Ratones , Estrés Oxidativo/efectos de los fármacos
9.
Eur J Clin Nutr ; 56(7): 674-9, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12080409

RESUMEN

OBJECTIVE: Several studies suggest that a fatty meal impairs flow-mediated vasodilation (FMD), a measure of endothelial function. We tested whether the impairment was greater for trans fats than for saturated fats. We did this because we previously showed that replacement of saturated fats by trans fats in a controlled diet decreased FMD after 4 weeks. DESIGN: We fed 21 healthy men two different test meals with 0.9-1.0 g fat/kg body weight in random order: one rich in saturated fatty acids (Sat), mainly from palm kernel fat, and one rich in trans fatty acids (Trans) from partially hydrogenated soy bean oil. The study was performed in our metabolic ward. We had complete data for both diets of 21 men. RESULTS: FMD increased from a fasting value of 2.3+/-2.0% of the baseline diameter to 3.0+/-1.7% after the Sat test meal (95% CI for change -0.33, 1.70) and from 2.7+/-2.3 to 3.1+/-2.0% after the Trans test meal (95% CI for change -0.57, 1.29). The increase after the Sat meal was 0.22 (-1.18-1.61) FMD% higher than after the Trans meal. Serum triacylglycerols increased by 0.46+/-0.36 mmol/l after the Sat test meal and by 0.68+/-0.59 mmol/l after the Trans test meal; a difference of 0.23 (0.07, 0.39) mmol/l. Serum HDL-cholesterol was hardly affected by the test meals. The activity of serum paraoxonase, an esterase bound to HDL, increased slightly after the two test meals but the difference between meals was not significant. CONCLUSION: FMD was not impaired and not different after test meals with saturated or trans fatty acids. Thus, differences in long-term effects of these fats are not caused by differences in acute effects on the vascular wall.


Asunto(s)
Ácidos Grasos Monoinsaturados/farmacología , Ácidos Grasos/farmacología , Periodo Posprandial/fisiología , Vasodilatación/efectos de los fármacos , Adulto , Arildialquilfosfatasa , Colesterol/sangre , HDL-Colesterol/sangre , Endotelio Vascular/efectos de los fármacos , Esterasas/sangre , Ayuno , Ácidos Grasos/administración & dosificación , Ácidos Grasos Monoinsaturados/administración & dosificación , Humanos , Masculino , Aceite de Soja , Triglicéridos/sangre
10.
Eur J Clin Nutr ; 55(11): 951-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11641743

RESUMEN

OBJECTIVE: To determine the effects of meals rich in thermally stressed safflower (TSAF) and olive (TSOL) oils on postprandial serum paraoxonase (PON1) arylesterase activity and low density lipoprotein (LDL) oxidation in patients with type 2 diabetes. DESIGN: A randomised cross-over study. SETTING: Diabetes clinic and general practice. SUBJECTS: Fourteen patients (six men and eight women) with type 2 diabetes, aged 48-67 y, glycated haemoglobin <10% and fasting blood glucose <11 mmol/l were recruited. INTERVENTIONS: Patients received a milkshake rich in TSAF or TSOL and at least a week later they received the alternate milkshake. These fats contained high levels of lipid oxidation and degradation products. Blood samples were taken fasted and 4 h after consumption of the milkshake. MAIN OUTCOME MEASURES: Serum PON1 activity and lag time in LDL oxidation. RESULTS: After the meal rich in TSOL, serum PON1 activity increased significantly in women (12 (2.22) micromol/ml/min, mean (95% confidence interval), P=0.03) and not in men (0 (-4.4) micromol/ml/min) during the postprandial period. The increase in PON1 activity after the TSOL meal was significantly (P=0.03) greater in women compared with men. In women, the increase in serum PON1 activity after the TSOL meal was significantly different (13 (1.25) micromol/ml/min, P=0.04) compared with the corresponding change (-1 micromol/ml/min) after the TSAF meal. The lag time in LDL oxidation and indices of oxidative stress and antioxidant capacity did not vary significantly during the meals. CONCLUSIONS: Meals rich in TSOL may increase postprandial serum PON1 activity in middle-aged and older diabetic women. This change is potentially anti-atherogenic and may favour the use of olive oil over polyunsaturated fats in the diet of patients with type 2 diabetes. SPONSORSHIP: The study was supported by a grant from the National Heart Foundation of New Zealand.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Esterasas/sangre , Lipoproteínas LDL/metabolismo , Aceites de Plantas/farmacología , Aceite de Cártamo/farmacología , Anciano , Arildialquilfosfatasa , Estudios Cruzados , Diabetes Mellitus Tipo 2/enzimología , Esterasas/efectos de los fármacos , Femenino , Calor , Humanos , Cinética , Lipoproteínas LDL/efectos de los fármacos , Masculino , Persona de Mediana Edad , Aceite de Oliva , Oxidación-Reducción , Estrés Oxidativo , Aceites de Plantas/administración & dosificación , Periodo Posprandial , Aceite de Cártamo/administración & dosificación , Factores Sexuales
11.
J Toxicol Environ Health A ; 63(4): 253-71, 2001 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-11437059

RESUMEN

Excessive dietary intake of sugars could alter various biotransformation processes and the pharmacological and toxicological properties of numerous xenobiotics. In the present study, the effects of glucose supplementation were examined on the neurotoxicity of the organophosphorus (OP) pesticide parathion (PS) and its active metabolite, paraoxon (PO), a potent inhibitor of acetylcholinesterase (AChE). Rats (n = 6-12/treatment group) were given free access to tap water or 15% glucose (w/v) in tap water beginning 7 d prior to OP toxicant exposure. Food, caloric intake, and body weight were measured daily. Animals were challenged with either PS (4.5, 9, or 18 mg/kg, sc) or PO (0.3 0.5, or 0.7 mg/kg, sc) and clinical signs of neurotoxicity (i.e., autonomic dysfunction, involuntary movements) were recorded daily for the following 13 d. Glucose feeding was associated with a dramatic drop (approximately 50%) in feed intake and an increase (approximately 20% in total caloric consumption over the 7 d prior to OP exposure. Functional toxicity associated with PS exposure was increased in glucose-fed (GF) rats, but the glucose diet had no apparent effect on clinical signs of toxicity following PO treatment. Glucose feeding increased the magnitude of AChE inhibition in the frontal cortex and plasma at lower dosages (i.e., 4.5 and 9 mg/kg) 3 d following PS treatment. Time-course studies (3, 7, and 11 d after PS exposure, 18 mg/kg, sc) indicated significantly greater brain and plasma AChE inhibition in glucose-fed animals at later time points. In contrast, glucose feeding had no effect on the degree of AChE inhibition following PO exposure. Neither liver microsomal oxidative desulfuration of PS, nor liver or plasma paraoxonase, nor liver or plasma carboxylesterase activities were measurably affected by glucose feeding. Downregulation of muscarinic receptors 7 d after PS exposure (18 mg/kg, sc) was more extensive in GF rats. It is postulated that excessiveglucose consumption decreases the intake of other dietary components, in particular amino acids, limiting the de novo synthesis of AChE and consequent recovery of synaptic transmission. Due to the shorter duration of inhibition following PO exposure, sponta neous reactivation of AChE may be more important than de novo protein synthesis in recovery of function, and thus with the effects of glucose feeding on its toxicity. Individuals that derive a large proportion of their calories from sugars may be at higher risk of acute toxicity from organophosphorus pesticides such as PS.


Asunto(s)
Inhibidores de la Colinesterasa/toxicidad , Glucosa/toxicidad , Síndromes de Neurotoxicidad/psicología , Paratión/toxicidad , Animales , Arildialquilfosfatasa , Conducta Animal/efectos de los fármacos , Biotransformación , Hidrolasas de Éster Carboxílico/sangre , Hidrolasas de Éster Carboxílico/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/enzimología , Inhibidores de la Colinesterasa/farmacocinética , Sinergismo Farmacológico , Ingestión de Alimentos/fisiología , Ingestión de Energía/fisiología , Esterasas/sangre , Esterasas/metabolismo , Masculino , Oxidación-Reducción , Paratión/farmacocinética , Ratas , Ratas Sprague-Dawley , Receptores Muscarínicos/metabolismo , Azufre/metabolismo
12.
Atherosclerosis ; 155(1): 71-8, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11223428

RESUMEN

In order to identify potential atherogenic properties of gas-phase cigarette smoke, we utilized an in vitro exposure model to determine whether the activities of several putative anti-atherogenic enzymes associated with plasma lipoproteins were compromised. Exposure of heparinized human plasma to gas-phase cigarette smoke produced a dose-dependent reduction in the activity of platelet-activating factor acetylhydrolase (PAF-AH). Reductions of nearly 50% in PAF-AH activity were observed following exposure to gas-phase smoke from four cigarettes over an 8-h period. During this time of exposure, lecithin:cholesterol acyltransferase (LCAT) was rendered almost completely inactive (>80%). In contrast, paraoxonase was totally unaffected by cigarette smoke. Supplementation of plasma with 1 mM reduced glutathione was found to protect both PAF-AH and LCAT from cigarette smoke, suggesting that cysteine modifications may have contributed to the inhibition of these two enzymes. To evaluate this possibility, we blocked the free cysteine residues of these enzymes with the reversible thiol-modifying reagent dithiobisnitrobenzoic acid (DTNB). Reversal of the DTNB-cysteine adducts following cigarette smoke exposures revealed that LCAT, but not PAF-AH, was protected. Moreover, high doses (1.0-10 mM) of acrolein and 4-hydroxynonenal, reactive aldehydic species associated with cigarette smoke, completely inhibited plasma LCAT activity, whereas PAF-AH was resistant to such exposures. Taken together, these results indicate a divergence regarding the underlying mechanism of PAF-AH and LCAT inhibition upon exposure to gas-phase cigarette smoke. While LCAT was sensitive to exposure to volatile aldehydic products involving, in part, cysteine and/or active site modifications, the enzyme PAF-AH exhibited an apparent resistance. The latter suggests that the active site of PAF-AH is in a microenvironment that lacks free cysteine residues and/or is shielded from volatile aldehydic combustion products. Based on these results, we propose that cigarette smoke may contribute to atherogenesis by inhibiting the activities of plasma PAF-AH and LCAT, but the nature of this inhibition differs for the enzymes.


Asunto(s)
Esterasas/sangre , Nicotiana , Fosfatidilcolina-Esterol O-Aciltransferasa/sangre , Fosfolipasas A/sangre , Plantas Tóxicas , Humo , 1-Alquil-2-acetilglicerofosfocolina Esterasa , Acroleína/farmacología , Aldehídos , Arildialquilfosfatasa , Ácido Ditionitrobenzoico/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Técnicas In Vitro , Reactivos de Sulfhidrilo/farmacología
13.
J Nutr ; 130(10): 2427-33, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11015468

RESUMEN

We examined the effects of dietary fats with specific fatty acid compositions, on serum paraoxonase (PON1) activity in rats. Male adult Sprague-Dawley rats were divided randomly into four dietary groups. One group received the control diet [AIN 93M with soybean oil (5 g/100 g diet)], whereas the remaining three groups received the modified control diet supplemented with (15 g/100 g diet) triolein, tripalmitin or fish oil, respectively. After 20 d, blood was obtained after overnight food deprivation and PON1 activity was determined. Serum lipids and lipid components of lipoproteins were also determined. Serum PON1 activity [micromol/(L.min)] was significantly (P: < 0.05) higher in triolein (98 +/- 6) and lower in fish oil (41 +/- 4), compared with tripalmitin-fed rats (63 +/- 11). Serum PON1 activity in tripalmitin-fed rats was comparable to that of controls (67 +/- 9). Serum PON1 activity correlated significantly with serum lecithin:cholesterol acyltransferase (LCAT) activity (r = 0.77, P: < 0.001) and was transported in blood principally in association with the denser subfraction of HDL, very high density lipoprotein (VHDL; d > 1.15 kg/L). Serum PON1 activity correlated strongly with serum lipids as well as lipids of VLDL, HDL and its subfractions. Multiple linear regression analysis, however, showed a significant relationship of serum PON1 activity, principally with the phospholipids of VHDL (r = 0.47, P: < 0.002). These data suggest that the modulation of serum PON1 activity by dietary fat may be mediated via the effect of the specific fatty acids on the synthesis and secretion of VHDL, the subfraction of HDL that transports the majority of PON1 in the blood.


Asunto(s)
Grasas de la Dieta/farmacología , Esterasas/sangre , Animales , Arildialquilfosfatasa , Peso Corporal , Colesterol/sangre , Ayuno , Ácidos Grasos/administración & dosificación , Aceites de Pescado/administración & dosificación , Lípidos/sangre , Lipoproteínas/sangre , Lipoproteínas HDL/sangre , Lipoproteínas VLDL/sangre , Masculino , Fosfolípidos/sangre , Ratas , Ratas Sprague-Dawley , Triglicéridos/administración & dosificación , Triglicéridos/sangre , Trioleína/administración & dosificación
14.
Arterioscler Thromb Vasc Biol ; 20(6): 1637-43, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10845883

RESUMEN

We studied the effect of hyperbaric oxygen (HBO) treatment on the extent of diet-induced accumulation of lipid oxidation products in rabbit plasma and tissues, on plasma paraoxonase activity, and on the extent of progression and regression of atherosclerotic lesions in the rabbit aorta. HBO treatment of cholesterol-fed rabbits dramatically reduces the development of arterial lesions despite having little or no effect on plasma or individual lipoprotein cholesterol concentrations. Compared with no treatment in cholesterol-fed animals, HBO treatment also substantially reduces the accumulation of lipid oxidation products (conjugated dienes, trienes, and thiobarbituric acid-reactive substances) in plasma, in the low density lipoprotein and high density lipoprotein fractions of plasma, in the liver, and in the aortic tissues. In addition, HBO treatment prevents the decrease in plasma paraoxonase activity observed in rabbits fed cholesterol-rich diets. Similarly, in regression studies, HBO treatment has no effect on the rate of plasma (or lipoprotein) cholesterol decline but significantly accelerates aortic lesion regression compared with no treatment. Direct measures of aortic cholesterol content support these morphological observations. On the basis of these results, we conclude that repeated, but relatively short, exposure to HBO induces an antioxidant defense mechanism(s) that is responsible for retarding the development or accelerating the regression of atherosclerotic lesions.


Asunto(s)
Arteriosclerosis/terapia , Oxigenoterapia Hiperbárica , Animales , Aorta/metabolismo , Aorta/patología , Arteriosclerosis/etiología , Arteriosclerosis/patología , Arildialquilfosfatasa , Colesterol/sangre , Colesterol en la Dieta/administración & dosificación , Esterasas/sangre , Peróxidos Lipídicos/sangre , Lipoproteínas HDL/sangre , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/sangre , Lipoproteínas LDL/metabolismo , Hígado/metabolismo , Masculino , Conejos , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
15.
Chem Biol Interact ; 119-120: 71-8, 1999 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-10421440

RESUMEN

Human serum paraoxonase/arylesterase (PON1, EC 3.1.8.1.) is a calcium-dependent enzyme which hydrolyzes a wide variety of organophosphates, including paraoxon, DFP, sarin and soman. Although the 3-D structure of PON has not yet been determined and its sequence shows no similarity with any other crystallized proteins, we undertook to identify some of its essential amino acid residues by two complementary approaches: group-specific labelling and site-directed mutagenesis. Group-specific labelling studies, performed on the purified native enzyme, indicated that one or more Trp, His and Asp/Glu are potentially important residues for PON activity. Based on these results, we identified some of these residues, conserved in the sequenced mammalian PON1, by site-directed mutagenesis. PON1 mutants were transiently expressed in 293T cells. The catalytic constants k(cat) and Km (relative to k(cat) and Km of the wild-type) determined with four different substrates (phenylacetate, paraoxon, diazoxon, chlorpyrifos oxon), were not significantly changed for the following mutants: W193A, W201A, W253A, H160N, H245N, H250N, H347N, E32A, E48A, D88A, D107A, D121A, D273A. By contrast, k(cat) was less than 1% for eight mutants: W280A, H114N, H133N, H154N, H242N, H284N, E52A and D53A. The essential amino acid residues identified in this work could be part of the PON1 active site, acting either as calcium ligands (E52 and D53?) or as substrate binding (W280?) or nucleophilic (His residues?) sites. However, we cannot rule out that the effects of mutations on catalytic properties resulted from a remote conformational change and/or misfolding of mutant proteins.


Asunto(s)
Aminoácidos Esenciales/sangre , Aminoácidos Esenciales/genética , Esterasas/sangre , Esterasas/genética , Aminoácidos Esenciales/metabolismo , Arildialquilfosfatasa , Bromosuccinimida/farmacología , Diciclohexilcarbodiimida/farmacología , Dietil Pirocarbonato/farmacología , Activación Enzimática , Esterasas/antagonistas & inhibidores , Humanos , Cinética , Mutagénesis Sitio-Dirigida , Conformación Proteica , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
16.
J Egypt Public Health Assoc ; 70(3-4): 431-47, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-17214168

RESUMEN

Male Wistar rats were injected by dimethoate (10 mg/0.5 ml) daily for 8 successive days. Controls received the same amount of saline., A group of 5 rats were anesthetized at 0, 2, 4, 6 and 8 days of injection. Blood was withdrawn from heart. serum lipid components and 4 species of serum esterases were assayed for each group. A general decrease in the activities of serum esterases was observed. A marked decrease also was observed in lipids profile during the 8 days course of experiment.


Asunto(s)
Inhibidores de la Colinesterasa/toxicidad , Dimetoato/toxicidad , Esterasas , Insecticidas/toxicidad , Metabolismo de los Lípidos/efectos de los fármacos , Acetilcolinesterasa/sangre , Acetilcolinesterasa/efectos de los fármacos , Animales , Biomarcadores/sangre , Peso Corporal/efectos de los fármacos , Butirilcolinesterasa/sangre , Butirilcolinesterasa/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Ingestión de Energía/efectos de los fármacos , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Esterasas/sangre , Esterasas/efectos de los fármacos , Inyecciones Intraperitoneales , Dosificación Letal Mediana , Masculino , Ratas , Ratas Wistar , Factores de Tiempo
17.
Br J Clin Pharmacol ; 36(5): 399-404, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12959286

RESUMEN

1. The aims of this study were two-fold. First, to define ranges of blood esterase activities in three groups, namely young subjects, fit community dwelling elderly and frail, chronically hospitalised elderly subjects, and second, to determine whether low blood esterase activities in the frail patients could be altered by increasing their nutritional intake. 2. Plasma cholinesterase, aspirin esterase, paraoxonase and phenylacetate esterase activities were all significantly lower in the frail elderly compared with the young and fit elderly volunteers. The activity of red blood cell esterase was not different in the frail elderly. 3. Fourteen frail elderly patients were randomly assigned to receive either hospital meal provision plus supplemental feeding with Build-up (Nestle) and Maxijul (SHS Ltd) or hospital provision alone for 8 weeks. Dietary intake was measured for all patients at the start of the study and at week 8. Measurements of blood esterase (cholinesterase, phenylacetate esterase, paraoxonase, aspirin esterase and red blood cell esterase), albumin and anthropometric indices (weight, triceps skinfold thickness and mid arm circumference) were made before the study and repeated at week 4 and 8. 4. There was a significant increase in plasma cholinesterase at week 4 (P < 0.05) but this was not statistically significant at week 8. There were no significant changes in any of the other esterase activities or anthropometric measurements. 5. We conclude that the lower esterase activities of the frail chronically hospitalised elderly do not respond to dietary supplementation for a period of 8 weeks with routinely available products. The hypothesis that lower esterase activities are the direct result of undernutrition which would be corrected by dietary supplementation has not been supported by this study.


Asunto(s)
Suplementos Dietéticos , Esterasas/sangre , Anciano , Peso Corporal , Ingestión de Energía , Femenino , Anciano Frágil , Hospitalización , Humanos , Masculino , Grosor de los Pliegues Cutáneos
18.
Vestn Khir Im I I Grek ; 140(4): 106-10, 1988 Apr.
Artículo en Ruso | MEDLINE | ID: mdl-2458652

RESUMEN

The examination of 41 patients with phlegmons of the face and neck has revealed a considerable activation of kininogenesis. The application of the RUVIB method in 29 patients who had the most severe course of the disease allowed protease inhibitors to be rejected even in cases with sepsis and mediastinitis, effects of RUVIB exerted the regulation of processes of kininogenesis with the help of endogenous mechanisms.


Asunto(s)
Transfusión de Sangre Autóloga , Sangre/efectos de la radiación , Celulitis (Flemón)/terapia , Calicreínas/sangre , Cininas/sangre , Rayos Ultravioleta , Adulto , Aprotinina/sangre , Celulitis (Flemón)/sangre , Terapia Combinada , Esterasas/sangre , Dermatosis Facial/sangre , Dermatosis Facial/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuello
19.
Biochem Med ; 32(3): 322-30, 1984 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6517876

RESUMEN

The characteristics of acid esterase from the patient with Wolman's disease, a rare familial lipidosis, were studied. Enzymatic analysis as well as mineral analysis were performed on the patient's liver, spleen, and adrenal glands. Acid esterase was low in the patient's leucocytes and other affected tissues. Further enzymatic study with subcellular fractions of the liver in both patient and control subject revealed that acid esterase was mostly localized in the membrane of lysosomes. The lysosomal esterase was unaffected by Ca2+, Mg2+, EDTA, E600 (microsomal esterase inhibitor), and it was less inhibited by NaCl than other fractions. Studies with those inhibitors showed that acid esterase has different properties compared to other lipases, such as lipoprotein lipase, adipose tissue lipase, and hepatic microsomal lipase. Studies with inhibitors also gave a negative view on a possible suppressive interaction of the high content of calcium in the target organs with acid esterase in Wolman's disease.


Asunto(s)
Esterasas/análisis , Errores Innatos del Metabolismo Lipídico/enzimología , Glándulas Suprarrenales/enzimología , Adulto , Calcio/análisis , Niño , Preescolar , Esterasas/sangre , Femenino , Humanos , Lactante , Leucocitos/enzimología , Errores Innatos del Metabolismo Lipídico/genética , Hígado/enzimología , Masculino , Minerales/análisis , Fósforo/análisis , Bazo/enzimología , Fracciones Subcelulares/enzimología
20.
Acta Paediatr Scand ; 64(2): 293-8, 1975 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1130188

RESUMEN

Phototherapy of newborn infants with hyperbilirubinemia was shown to result in an increase in hematocrit values and in the activity of the erythrocyte enzyme acetylsalicylic acid esterase. The elevation of the enzyme activity also could be produced in light-treated rabbits and in vitro after illumination of blood from adult volunteers. The binding of bilirubin to serum albumin and of salicylate to plasma proteins did not alter, nor did the concentrations of albumin or total proteins in plasma. It is concluded that light does not increase the unbound fraction of bilirubin in blood.


Asunto(s)
Bilirrubina/sangre , Esterasas/sangre , Ictericia Neonatal/terapia , Fototerapia , Salicilatos/sangre , Animales , Aspirina/sangre , Proteínas Sanguíneas/metabolismo , Hematócrito , Humanos , Recién Nacido , Ictericia Neonatal/sangre , Ictericia Neonatal/enzimología , Masculino , Unión Proteica , Conejos , Albúmina Sérica/metabolismo
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