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1.
Bone Marrow Transplant ; 52(6): 859-862, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28287644

RESUMEN

Acute GvHD (aGvHD) is a life-threatening complication of hematopoietic stem cell transplantation. Frontline therapy for aGvHD consists of corticosteroid administration. However, ∼25% of the patients have a steroid-refractory disease, a sign of poor prognosis. An alternative therapy for steroid-refractory aGvHD is infusion of mesenchymal stromal cells (MSCs). Herein, we report the results of 46 patients treated with MSC infusion as salvage therapy for steroid-refractory aGvHD III/IV (78% grade IV). Patients received a median cumulative dose of MSCs of 6.81 × 106/kg (range, 0.98-29.78 × 106/kg) in a median of 3 infusions (range, 1-7). Median time between the onset of aGvHD and the first MSC infusion was 25.5 days (range, 6-153). Of the patients, 50% (23/46) presented clinical improvement. Of these, 3 patients (13%) had complete response, 14 (61%) had partial response and 6 (26%) had transient partial response. The estimated probability of survival at 2s year was 17.4%. Only 2 patients (4.3%) presented acute transient side effects (nausea/vomiting and blurred vision) during cell infusion. No patient had late or severe side effects because of MSC infusion. These results suggest that this therapeutic modality is safe and should be considered for steroid-refractory aGvHD, especially in countries where other second-line agents are less available.


Asunto(s)
Enfermedad Injerto contra Huésped , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Trasplante de Células Madre Mesenquimatosas , Enfermedad Aguda , Adolescente , Adulto , Anciano , Aloinjertos , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Enfermedad Injerto contra Huésped/mortalidad , Enfermedad Injerto contra Huésped/terapia , Neoplasias Hematológicas/mortalidad , Neoplasias Hematológicas/terapia , Humanos , Lactante , Masculino , Persona de Mediana Edad , Esteroides/administración & dosificación , Tasa de Supervivencia
2.
Cell Biochem Funct ; 29(7): 543-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21989892

RESUMEN

Pulmonary arterial hypertension (PAH) is a disease that increases the pulmonary vascular resistance, causing hypertrophy and subsequent right heart failure. Oxidative stress is involved in the pathogenesis of PAH, and estrogen is considered an antioxidant. Thus, the aim of this study was to test the hypothesis that estrogen could attenuate PAH by modulating oxidative stress. Female Wistar rats were ovariectomized or suffered the surgery simulation (sham). After 7 days, subcutaneous pellets with 17ß-estradiol or sunflower oil were implanted. At this time, PAH was induced by means of a single dose of monocrotaline (MCT) (60 mg·kg(-1) i.p.). The experimental groups were as follows: (1) sham, (2) sham + MCT, (3) ovariectomy (O), (4) ovariectomy + MCT (OM), (5) ovariectomy + estrogen replacement + MCT (ORM). Hemodynamic measurements were performed 21 days after MCT or saline. Nonovariectomized animals were assessed in the stage of diestrus. Afterwards, the rats were killed to collect the heart, the lung and the liver to evaluate morphometry. Samples of the right ventricle were used to analyse the reduced glutathione : oxidized glutathione ratio. Lung congestion in the OM group, which was decreased in the ORM group, was observed. Right ventricle end-diastolic pressure was increased in the OM and the ORM groups. The glutathione ratio decreased in the groups O, OM and ORM. The data suggest that estrogen can exert great influence on the cellular redox balance. The maintenance of physiological estrogen levels may help to avoid the appearance of pulmonary oedema, characteristic of this model of PAH, and right ventricular failure.


Asunto(s)
Estradiol/farmacología , Hipertensión Pulmonar/tratamiento farmacológico , Estrés Oxidativo , Animales , Western Blotting , Peso Corporal , Diestro/fisiología , Estradiol/administración & dosificación , Femenino , Glutatión/metabolismo , Ventrículos Cardíacos/fisiopatología , Hemodinámica , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/fisiopatología , Monocrotalina/administración & dosificación , Monocrotalina/efectos adversos , Ovariectomía , Aceites de Plantas/administración & dosificación , Arteria Pulmonar/fisiopatología , Ratas , Ratas Wistar , Aceite de Girasol
3.
Cell Biochem Funct ; 29(7): 617-23, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21989893

RESUMEN

This study was conducted to analyse the redox status and redox-sensitive proteins that may contribute to a non-genomic mechanism of cardiac hypertrophy induction by hyperthyroidism. Wistar rats, treated with L-thyroxine (T4) during 2 weeks (12 mg·l(-1) in drinking water), presented cardiac hypertrophy (68% higher than control), without signals of liver or lung congestion. Myocardial reduction of the reduced glutathione: oxidized glutathione (GSSG) ratio (45%) (redox status) and elevation in hydrogen peroxide concentration (H(2) O(2) ) (28%) were observed in hyperthyroid as compared with the control. No significant difference was found in thioredoxin (Trx), Trx reductase activity and Nrf2 (a transcriptional factor) protein expression between groups. Redox-sensitive proteins, quantified using Western blot, presented the following results: increased p-ERK: total extracellular-regulated kinase (ERK) (200%) and Bax:Bcl-2 (62%) ratios and reduced total-Akt (63%) and p-Akt (53%) expressions in the hyperthyroid rats as compared with the control. The redox imbalance, associated with increased immunocontent of a protein related to maladaptative growth (ERK) and reduced immunocontent of protein related to cytoprotection/survival (Akt), may suggest that the molecular scenario could favour the decompensation process of cardiac hypertrophy induced by experimental hyperthyroidism.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Cardiomegalia/inducido químicamente , Hipertiroidismo/inducido químicamente , Tiroxina/efectos adversos , Animales , Western Blotting , Cardiomegalia/patología , Muerte Celular , Agua Potable/administración & dosificación , Glutatión/metabolismo , Disulfuro de Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Hipertiroidismo/patología , Sistema de Señalización de MAP Quinasas , Masculino , Modelos Animales , Oxidación-Reducción , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Wistar , Tiorredoxinas/metabolismo , Tiroxina/administración & dosificación , Tiroxina/farmacología , Proteína X Asociada a bcl-2/metabolismo
4.
Braz. j. med. biol. res ; 42(10): 892-901, Oct. 2009. ilus, tab
Artículo en Inglés | LILACS | ID: lil-526182

RESUMEN

Shock and resuscitation render patients more susceptible to acute lung injury due to an exacerbated immune response to subsequent inflammatory stimuli. To study the role of innate immunity in this situation, we investigated acute lung injury in an experimental model of ischemia-reperfusion (I-R) followed by an early challenge with live bacteria. Conscious rats (N = 8 in each group) were submitted to controlled hemorrhage and resuscitated with isotonic saline (SS, 0.9 percent NaCl) or hypertonic saline (HS, 7.5 percent NaCl) solution, followed by intratracheal or intraperitoneal inoculation of Escherichia coli. After infection, toll-like receptor (TLR) 2 and 4 mRNA expression was monitored by RT-PCR in infected tissues. Plasma levels of tumor necrosis factor α and interleukins 6 and 10 were determined by ELISA. All animals showed similar hemodynamic variables, with mean arterial pressure decreasing to nearly 40 mmHg after bleeding. HS or SS used as resuscitation fluid yielded equal hemodynamic results. Intratracheal E. coli inoculation per se induced a marked neutrophil infiltration in septa and inside the alveoli, while intraperitoneal inoculation-associated neutrophils and edema were restricted to the interseptal space. Previous I-R enhanced lung neutrophil infiltration upon bacterial challenge when SS was used as reperfusion fluid, whereas neutrophil influx was unchanged in HS-treated animals. No difference in TLR expression or cytokine secretion was detected between groups receiving HS or SS. We conclude that HS is effective in reducing the early inflammatory response to infection after I-R, and that this phenomenon is achieved by modulation of factors other than expression of innate immunity components.


Asunto(s)
Animales , Masculino , Ratas , Lesión Pulmonar Aguda/inmunología , Infecciones por Escherichia coli/inmunología , Inflamación/inmunología , Daño por Reperfusión/inmunología , Solución Salina Hipertónica/uso terapéutico , Choque Hemorrágico/tratamiento farmacológico , Enfermedad Aguda , Lesión Pulmonar Aguda/sangre , Lesión Pulmonar Aguda/microbiología , Citocinas/sangre , Modelos Animales de Enfermedad , Inmunidad Innata , Inflamación/sangre , Inflamación/tratamiento farmacológico , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ARN Mensajero/sangre , Choque Hemorrágico/inmunología , /sangre
5.
Braz J Med Biol Res ; 42(10): 892-901, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19787146

RESUMEN

Shock and resuscitation render patients more susceptible to acute lung injury due to an exacerbated immune response to subsequent inflammatory stimuli. To study the role of innate immunity in this situation, we investigated acute lung injury in an experimental model of ischemia-reperfusion (I-R) followed by an early challenge with live bacteria. Conscious rats (N = 8 in each group) were submitted to controlled hemorrhage and resuscitated with isotonic saline (SS, 0.9% NaCl) or hypertonic saline (HS, 7.5% NaCl) solution, followed by intratracheal or intraperitoneal inoculation of Escherichia coli. After infection, toll-like receptor (TLR) 2 and 4 mRNA expression was monitored by RT-PCR in infected tissues. Plasma levels of tumor necrosis factor alpha and interleukins 6 and 10 were determined by ELISA. All animals showed similar hemodynamic variables, with mean arterial pressure decreasing to nearly 40 mmHg after bleeding. HS or SS used as resuscitation fluid yielded equal hemodynamic results. Intratracheal E. coli inoculation per se induced a marked neutrophil infiltration in septa and inside the alveoli, while intraperitoneal inoculation-associated neutrophils and edema were restricted to the interseptal space. Previous I-R enhanced lung neutrophil infiltration upon bacterial challenge when SS was used as reperfusion fluid, whereas neutrophil influx was unchanged in HS-treated animals. No difference in TLR expression or cytokine secretion was detected between groups receiving HS or SS. We conclude that HS is effective in reducing the early inflammatory response to infection after I-R, and that this phenomenon is achieved by modulation of factors other than expression of innate immunity components.


Asunto(s)
Lesión Pulmonar Aguda/inmunología , Infecciones por Escherichia coli/inmunología , Inflamación/inmunología , Daño por Reperfusión/inmunología , Solución Salina Hipertónica/uso terapéutico , Choque Hemorrágico/tratamiento farmacológico , Enfermedad Aguda , Lesión Pulmonar Aguda/sangre , Lesión Pulmonar Aguda/microbiología , Animales , Citocinas/sangre , Modelos Animales de Enfermedad , Inmunidad Innata , Inflamación/sangre , Inflamación/tratamiento farmacológico , Masculino , ARN Mensajero/sangre , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Choque Hemorrágico/inmunología , Receptor Toll-Like 2/sangre
6.
Thorac Cardiovasc Surg ; 57(5): 309-11, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19629897

RESUMEN

The overproduction of reactive oxygen species plays an important role in the cascade of events during lung ischemia-reperfusion leading to graft failure. An evaluation of the peripheral markers of oxidative stress and antioxidant enzyme activities was carried out after reperfusion in a rat lung transplant model. The decrease in lipid peroxidation immediately after transplantation ( P < 0.05) may suggest an adaptative response and/or a protective effect of low potassium dextran against lipid peroxidation through natural scavenging mechanisms.


Asunto(s)
Eritrocitos/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Peroxidación de Lípido/efectos de los fármacos , Trasplante de Pulmón , Soluciones Preservantes de Órganos/farmacología , Estrés Oxidativo/efectos de los fármacos , Daño por Reperfusión/prevención & control , Animales , Catalasa/metabolismo , Dextranos/farmacología , Eritrocitos/enzimología , Glucosa/farmacología , Masculino , Modelos Animales , Ratas , Ratas Wistar , Daño por Reperfusión/sangre , Superóxido Dismutasa/metabolismo , Factores de Tiempo
7.
J Mol Endocrinol ; 41(6): 423-30, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18787053

RESUMEN

This study was conducted to test whether oxidative stress activates the intracellular protein kinase B (AKT1) signaling pathway, which culminates with cardiac hypertrophy in experimental hyperthyroidism. Male Wistar rats were divided into four groups: control, vitamin E, thyroxine (T(4)), and T(4)+vitamin E. Hyperthyroidism was induced by T(4) administration (12 mg/l in drinking water for 28 days). Vitamin E treatment was given during the same period via s.c. injections (20 mg/kg per day). Morphometric and hemodynamic parameters were evaluated at the end of the 4-week treatment period. Protein oxidation, redox state (reduced glutathione, GSH/glutathione dissulfide, GSSG), vitamin C, total radical-trapping antioxidant potential (TRAP), hydrogen peroxide (H2O2), and nitric oxide metabolites (NO(X)) were measured in heart homogenates. The p-AKT1/AKT1 ratio, p-glycogen-synthase kinase (GSK)3B/GSK3B ratio, FOS, and JUN myocardial protein expression were also quantified by western blot after 4 weeks. Increases in biochemical parameters, such as protein oxidation (41%), H2O2 (62%), and NO(X) (218%), and increase in the left ventricular end-diastolic pressure were observed in the T(4) group. T(4) treatment also caused a decrease in GSH/GSSG ratio (83%), vitamin C (34%), and TRAP (55%). These alterations were attenuated by vitamin E administration to the hyperthyroid rats. Expression of p-AKT1/AKT1, p-GSK3B/GSK3B, FOS, and JUN were elevated in the T(4) group (by 69, 37, 130, and 33% respectively), whereas vitamin E administration promoted a significant reduction in their expression. These results indicate that oxidative stress plays an important role in cardiac hypertrophy, and suggest redox activation of AKT1 and JUN/FOS signaling pathways with H2O2 acting as a possible intracellular mediator in this adaptive response to experimental hyperthyroidism.


Asunto(s)
Cardiomegalia/etiología , Modelos Animales de Enfermedad , Hipertiroidismo/complicaciones , Transducción de Señal , Animales , Ácido Ascórbico/metabolismo , Western Blotting , Cardiomegalia/metabolismo , Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Masculino , Oxidación-Reducción , Ratas , Ratas Wistar , Tiroxina/sangre
8.
Mol Cell Biochem ; 303(1-2): 89-95, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17447016

RESUMEN

Thyroxine can cause cardiac hypertrophy by activating growth factors, such as IGF-I (insulin-like growth factor-I). Since oxidative stress is enhanced in the hyperthyroidism, it would control protein expression involved in this hypertrophy. Male Wistar rats were divided into four groups: (I) control, (II) vitamin E-supplemented (20 mg/kg/day subcutaneous), (III) hyperthyroid (thyroxine 12 mg/l, in drinking water), and (IV) hyperthyroid + vitamin E. After 4 weeks, the contractility and relaxation indexes of left ventricle (LV), and cardiac mass were increased by 54%, 60%, and 60%, respectively, in hyperthyroid group. An increase in lipid peroxidation (around 40%), and a decrease in total glutathione (by 20%) was induced by thyroxine and avoided by vitamin E administration. Superoxide dismutase (SOD) and glutathione-S-transferase (GST) activities were increased (by 83% and 54%, respectively) in hyperthyroid, and vitamin E avoided changes in SOD. Protein expression of SOD, GST, and IGF-I receptor (IGF-IR) were increased (by 87%, 84%, and 60%, respectively) by thyroxine, and vitamin E promoted a significant reduction in SOD and IGF-IR expression (by 36% and 17%, respectively). These results indicate that oxidative stress is involved in cardiac hypertrophy, and suggest a role for IGF-IR as a mediator of this adaptive response in experimental hyperthyroidism.


Asunto(s)
Cardiomegalia/patología , Peroxidación de Lípido/efectos de los fármacos , Estrés Oxidativo , Receptor IGF Tipo 1/metabolismo , Tiroxina/farmacología , Animales , Antioxidantes/farmacología , Peso Corporal , Cardiomegalia/inducido químicamente , Cardiomegalia/metabolismo , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Transferasa/metabolismo , Masculino , Oxidación-Reducción , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo , Tiroxina/sangre , Vitamina E/farmacología
9.
Braz J Med Biol Res ; 39(6): 767-72, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16751982

RESUMEN

The present study was designed to evaluate the time course changes in peripheral markers of oxidative stress in a chronic HgCl2 intoxication model. Twenty male adult Wistar rats were treated subcutaneously daily for 30 days and divided into two groups of 10 animals each: Hg, which received HgCl2 (0.16 mg kg(-1) day(-1)), and control, receiving the same volume of saline solution. Blood was collected at the first, second and fourth weeks of Hg administration to evaluate lipid peroxidation (LPO), total radical trapping antioxidant potential (TRAP), and superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and catalase (CAT). HgCl2 administration induced a rise (by 26%) in LPO compared to control (143 +/- 10 cps/mg hemoglobin) in the second week and no difference was found at the end of the treatment. At that time, GST and GPx were higher (14 and 24%, respectively) in the Hg group, and Cu,Zn-SOD was lower (54%) compared to control. At the end of the treatment, Cu,Zn-SOD and CAT were higher (43 and 10%, respectively) in the Hg group compared to control (4.6 +/- 0.3 U/mg protein; 37 +/- 0.9 pmol/mg protein, respectively). TRAP was lower (69%) in the first week compared to control (43.8 +/- 1.9 mM Trolox). These data provide evidence that HgCl2 administration is accompanied by systemic oxidative damage in the initial phase of the process, which leads to adaptive changes in the antioxidant reserve, thus decreasing the oxidative injury at the end of 30 days of HgCl2 administration. These results suggest that a preventive treatment with antioxidants would help to avoid oxidative damage in subjects with chronic intoxication.


Asunto(s)
Antioxidantes/análisis , Eritrocitos/enzimología , Peroxidación de Lípido/efectos de los fármacos , Cloruro de Mercurio/envenenamiento , Estrés Oxidativo/efectos de los fármacos , Peroxidasas/sangre , Animales , Antioxidantes/metabolismo , Biomarcadores/sangre , Enfermedad Crónica , Modelos Animales de Enfermedad , Luminiscencia , Masculino , Peroxidasas/metabolismo , Ratas , Ratas Wistar , Factores de Tiempo
10.
Braz. j. med. biol. res ; 39(6): 767-772, June 2006. ilus, tab
Artículo en Inglés | LILACS | ID: lil-428268

RESUMEN

The present study was designed to evaluate the time course changes in peripheral markers of oxidative stress in a chronic HgCl2 intoxication model. Twenty male adult Wistar rats were treated subcutaneously daily for 30 days and divided into two groups of 10 animals each: Hg, which received HgCl2 (0.16 mg kg-1 day-1), and control, receiving the same volume of saline solution. Blood was collected at the first, second and fourth weeks of Hg administration to evaluate lipid peroxidation (LPO), total radical trapping antioxidant potential (TRAP), and superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and catalase (CAT). HgCl2 administration induced a rise (by 26 percent) in LPO compared to control (143 ± 10 cps/mg hemoglobin) in the second week and no difference was found at the end of the treatment. At that time, GST and GPx were higher (14 and 24 percent, respectively) in the Hg group, and Cu,Zn-SOD was lower (54 percent) compared to control. At the end of the treatment, Cu,Zn-SOD and CAT were higher (43 and 10 percent, respectively) in the Hg group compared to control (4.6 ± 0.3 U/mg protein; 37 ± 0.9 pmol/mg protein, respectively). TRAP was lower (69 percent) in the first week compared to control (43.8 ± 1.9 mM Trolox). These data provide evidence that HgCl2 administration is accompanied by systemic oxidative damage in the initial phase of the process, which leads to adaptive changes in the antioxidant reserve, thus decreasing the oxidative injury at the end of 30 days of HgCl2 administration. These results suggest that a preventive treatment with antioxidants would help to avoid oxidative damage in subjects with chronic intoxication.


Asunto(s)
Animales , Masculino , Ratas , Antioxidantes/análisis , Eritrocitos/enzimología , Peroxidación de Lípido/efectos de los fármacos , Cloruro de Mercurio/envenenamiento , Estrés Oxidativo/efectos de los fármacos , Peroxidasas/sangre , Antioxidantes/metabolismo , Biomarcadores/sangre , Enfermedad Crónica , Modelos Animales de Enfermedad , Luminiscencia , Peroxidasas/metabolismo , Ratas Wistar , Factores de Tiempo
11.
Mol Cell Endocrinol ; 249(1-2): 133-9, 2006 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-16574313

RESUMEN

Hyperthyroidism was induced in rats by l-thyroxine administration (12 mg/L in drinking water, 4 weeks). Animals were assessed hemodynamically, and heart, lung, and liver morphometry were performed. Lipid peroxidation (LPO) and protein oxidation (carbonyls) were measured in heart homogenates. It was quantified glutathione (GSH) metabolism, and antioxidant enzyme activities its and protein expression (by Western blot). At the end of treatment, it was observed cardiac hypertrophy, elevation of left ventricular systolic and end diastolic pressures, lung and liver congestion. LPO and carbonyls were increased in the hyperthyroid group, and GSH was decreased by 46% in the fourth week. Myocardial oxidative stress time course analysis revealed that it was increased in the second week of treatment. Antioxidant enzyme activities elevation was accompanied by protein expression induction in the hyperthyroid group in the fourth week. These results imply that hyperthyroidism generates myocardial dysfunction associated with oxidative stress inducing antioxidant enzyme activities and protein expression.


Asunto(s)
Antioxidantes/metabolismo , Glutatión/metabolismo , Hipertiroidismo/metabolismo , Miocardio/enzimología , Animales , Catalasa/metabolismo , Glutatión Transferasa/metabolismo , Cardiopatías/complicaciones , Hipertiroidismo/inducido químicamente , Hipertiroidismo/complicaciones , Peroxidación de Lípido , Miocardio/metabolismo , Oxidación-Reducción , Ratas , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo , Tiroxina
12.
Braz J Med Biol Res ; 35(9): 1075-81, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12219179

RESUMEN

The purpose of the present study was to examine myocardial antioxidant and oxidative stress changes in male and female rats in the presence of physiological sex hormone concentrations and after castration. Twenty-four 9-week-old Wistar rats were divided into four groups of 6 animals each: 1) sham-operated females, 2) castrated females, 3) sham-operated males, and 4) castrated males. When testosterone and estrogen levels were measured by radioimmunoassay, significant differences were observed between the castrated and control groups (both males and females), demonstrating the success of castration. Progesterone and catalase levels did not change in any group. Control male rats had higher levels of glutathione peroxidase (50%) and lower levels of superoxide dismutase (SOD, 14%) than females. Control females presented increased levels of SOD as compared to the other groups. After castration, SOD activity decreased by 29% in the female group and by 14% in the male group as compared to their respective controls. Lipid peroxidation (LPO) was assessed to evaluate oxidative damage to cardiac membranes by two different methods, i.e., TBARS and chemiluminescence. LPO was higher in male controls compared to female controls when evaluated by both methods, TBARS (360%) and chemiluminescence (46%). Castration induced a 200% increase in myocardial damage in females as determined by TBARS and a 20% increase as determined by chemiluminescence. In males, castration did not change LPO levels. These data suggest that estrogen may have an antioxidant role in heart muscle, while testosterone does not.


Asunto(s)
Antioxidantes/metabolismo , Hormonas Esteroides Gonadales/metabolismo , Miocardio/enzimología , Estrés Oxidativo , Análisis de Varianza , Animales , Castración , Femenino , Depuradores de Radicales Libres/análisis , Depuradores de Radicales Libres/metabolismo , Glutatión Peroxidasa/análisis , Glutatión Peroxidasa/metabolismo , Peroxidación de Lípido/fisiología , Mediciones Luminiscentes , Masculino , Miocardio/patología , Ratas , Ratas Wistar , Superóxido Dismutasa/análisis , Superóxido Dismutasa/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico
13.
Braz. j. med. biol. res ; 35(9): 1075-1081, Sept. 2002. tab, graf
Artículo en Inglés | LILACS | ID: lil-325903

RESUMEN

The purpose of the present study was to examine myocardial antioxidant and oxidative stress changes in male and female rats in the presence of physiological sex hormone concentrations and after castration. Twenty-four 9-week-old Wistar rats were divided into four groups of 6 animals each: 1) sham-operated females, 2) castrated females, 3) sham-operated males, and 4) castrated males. When testosterone and estrogen levels were measured by radioimmunoassay, significant differences were observed between the castrated and control groups (both males and females), demonstrating the success of castration. Progesterone and catalase levels did not change in any group. Control male rats had higher levels of glutathione peroxidase (50 percent) and lower levels of superoxide dismutase (SOD, 14 percent) than females. Control females presented increased levels of SOD as compared to the other groups. After castration, SOD activity decreased by 29 percent in the female group and by 14 percent in the male group as compared to their respective controls. Lipid peroxidation (LPO) was assessed to evaluate oxidative damage to cardiac membranes by two different methods, i.e., TBARS and chemiluminescence. LPO was higher in male controls compared to female controls when evaluated by both methods, TBARS (360 percent) and chemiluminescence (46 percent). Castration induced a 200 percent increase in myocardial damage in females as determined by TBARS and a 20 percent increase as determined by chemiluminescence. In males, castration did not change LPO levels. These data suggest that estrogen may have an antioxidant role in heart muscle, while testosterone does not


Asunto(s)
Animales , Masculino , Femenino , Ratas , Antioxidantes , Hormonas Esteroides Gonadales , Miocardio , Estrés Oxidativo , Análisis de Varianza , Castración , Depuradores de Radicales Libres , Glutatión Peroxidasa , Peroxidación de Lípido , Mediciones Luminiscentes , Miocardio , Ratas Wistar , Superóxido Dismutasa , Sustancias Reactivas al Ácido Tiobarbitúrico
14.
Liver ; 22(1): 35-42, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11906617

RESUMEN

AIMS/BACKGROUND: Cellular and extracellular volume changes caused by ATP were investigated in the liver as well as the possible formation of diffusion barriers, which could be responsible for some of its metabolic effects. METHODS: The experimental system was the bivascularly perfused rat liver. [(14)C]Sucrose and [(3)H]water were simultaneously injected into either the portal vein or the hepatic artery. Mean transit times, distribution spaces, variances and linear superimpositions were calculated. RESULTS: In the portal system, ATP reduced the transit time in the great vessels, had little or no effect on sinusoidal and cellular spaces, but impaired the flow-limited distribution of both [(14)C]sucrose and [(3)H]water. In the arterial bed ATP infused into either the portal vein or the hepatic artery produced vasodilation and increased the aqueous extra-sucrose space. These effects were inhibited by Nomega-nitro-L-arginine methyl ester infused into the hepatic artery. CONCLUSIONS: Sucrose and extra-sucrose space changes caused in the arterial bed by portally infused ATP are most probably analogous to the transhepatic vasodilation effect already described for the rabbit liver. Impairment of flow-limited distribution of tracers in the sinusoidal bed indicates that ATP induces the formation of permeability barriers, which could be responsible for some of its metabolic effects.


Asunto(s)
Adenosina Trifosfato/farmacología , Permeabilidad de la Membrana Celular/efectos de los fármacos , Espacio Extracelular/efectos de los fármacos , Hígado/efectos de los fármacos , Animales , Permeabilidad de la Membrana Celular/fisiología , Antagonismo de Drogas , Espacio Extracelular/metabolismo , Arteria Hepática/efectos de los fármacos , Arteria Hepática/fisiología , Hígado/irrigación sanguínea , Hígado/metabolismo , Circulación Hepática/efectos de los fármacos , Circulación Hepática/fisiología , Masculino , NG-Nitroarginina Metil Éster/farmacología , Perfusión , Vena Porta/efectos de los fármacos , Vena Porta/fisiología , Ratas , Ratas Wistar , Sacarosa/metabolismo , Distribución Tisular , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Agua/metabolismo
15.
Mol Cell Biochem ; 195(1-2): 207-17, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10395085

RESUMEN

The heterogeneity of the liver parenchyma in relation to uric acid production from adenosine was investigated using the bivascularly perfused rat liver in the anterograde and retrograde modes. Adenosine was infused in livers from fed rats during 20 min at four different concentrations (20, 50, 100 and 200 microM) according to four experimental protocols as follows: (A) anterograde perfusion, with adenosine infusion into the portal vein; (B) anterograde perfusion, with adenosine in the hepatic artery, (C) retrograde perfusion, with adenosine in the hepatic vein; (D) retrograde perfusion, with adenosine in the hepatic artery. With protocols A, B, and D uric acid production from adenosine was always characterized by initial bursts followed by progressive decreases toward smaller steady-states. With protocol C the initial burst was present only when 200 microM adenosine was infused. The initial bursts in uric acid production were accompanied by simultaneous increases in the ratio of uric acid production/adenosine uptake rate. These initial bursts are thus representing increments in the production of uric acid that are not corresponded by similar increments in the metabolic uptake rates of adenosine. Global analysis of uric acid production revealed that the final steady-state rates were approximately equal for all infusion rates with protocols A, B and C, but smaller with protocol D. This difference, however, can be explained in terms of the differences in accessible cellular spaces, which are much smaller when protocol D is employed. When the analysis was performed in terms of the extra amounts of uric acid produced during the infusion of adenosine, where the initial bursts are also taken into account, different dose-response curves were found for each experimental protocol. These differences cannot be explained in terms of the accessible cell spaces and they are likely to reflect regional heterogeneities. From the various dose-response curves and from the known characteristics of the microcirculation of the rat liver it can be concluded that the initial bursts in uric acid production are generated in periportal hepatocytes. The reason for this heterogeneity could be related to the metabolic effects of adenosine, especially to oxygen uptake inhibition, which is likely to produce changes in the ATP/AMP ratios.


Asunto(s)
Adenosina/metabolismo , Hígado/metabolismo , Perfusión , Ácido Úrico/metabolismo , Adenosina/administración & dosificación , Animales , Arteria Hepática/metabolismo , Venas Hepáticas/metabolismo , Infusiones Intravenosas , Hígado/irrigación sanguínea , Hígado/química , Masculino , Consumo de Oxígeno , Perfusión/métodos , Vena Porta/metabolismo , Ratas , Ratas Wistar
16.
Biochem Pharmacol ; 58(3): 397-409, 1999 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-10424758

RESUMEN

The heterogeneity of the liver parenchyma in relation to the metabolic response to adenosine was investigated using the bivascularly perfused rat liver in the anterograde and retrograde modes. Adenosine was infused into livers from fed rats according to four experimental protocols: (A) anterograde perfusion, adenosine via the portal vein; (B) anterograde perfusion, adenosine via the hepatic artery; (C) retrograde perfusion, adenosine via the hepatic vein; and (D) retrograde perfusion, adenosine via the hepatic artery. Due to the very pronounced concentration gradients generated by metabolic transformation, the infused adenosine attained maximal concentrations in different regions with each experimental protocol. The sinusoidal mean transit times (t(s)) were not changed by adenosine in anterograde perfusion, but were increased in retrograde perfusion. It was concluded that the vasoconstrictive elements are localized essentially in the presinusoidal region. Glucose release stimulation presented two kinetic components. The first one was rapid in both onset and decay with a peak around 30 sec; the second one developed more slowly (several minutes). The factors of the first kinetic component are possibly generated in the presinusoidal region or in the first periportal cells. The initial decrease in oxygen consumption seemed to be localized in the region just after the intrasinusoidal confluence of the ramifications of the portal vein and hepatic artery. Indomethacin decreased glucose release stimulation by adenosine in both anterograde and retrograde perfusion only when DMSO was the vehicle. The participation of eicosanoids in the generation of the effects of adenosine seems to be less important than hitherto believed.


Asunto(s)
Adenosina/farmacología , Hígado/efectos de los fármacos , Vasodilatadores/farmacología , Adenosina/metabolismo , Animales , Interacciones Farmacológicas , Eicosanoides/farmacología , Glucosa/metabolismo , Hemodinámica/efectos de los fármacos , Indometacina/farmacología , Cinética , Hígado/fisiología , Masculino , Oxígeno/metabolismo , Perfusión , Ratas , Ratas Wistar , Vasodilatadores/metabolismo
17.
J Bras Ginecol ; 95(7): 293-6, 1985.
Artículo en Portugués | MEDLINE | ID: mdl-12341404

RESUMEN

PIP: 500 sexually active women in Brazil aged 15-50 were interviewed to study their use of contraceptives. For the 350 who used contraceptives, the survey evaluated their level of education, marital status, incidence of pregnancy, and the number of abortions performed. The level of education had little effect on the choice of birth control methods. Women with 1 sex partner were more preoccupied with the use of birth control than women who had casual sex with more than 1 partner. The younger women in the group, whether or not they used birth control, had greater frequency of abortions. The preferred method of contraception was the pill, and of the women who took the pill, almost 1/2 did so without a doctor's prescription. 42% of the same group reportedf suffering side effects due to pill use. Since induced abortions are illegal in Brazil, it is certain that the information given is inaccurate. Other methods of birth control also had drawbacks. The early withdrawal method did nothing for the couple's sexual gratification, and was not an effective method of birth control. The rhythm method was rarely used, and could also be dangerous as far as effectiveness. The IUD, which has proven to be very effective in developed nations, was not widely used by this group because it was considered troublesome. It is clear from this report that all means need to be implemented to make birth control accessible to all levels of the population. Failure to utilize birth control methods on moral or religious grounds will cause an increase in abortions, many of which will be performed by unqualified people. The denial of birth control will lead to disastrous consequences.^ieng


Asunto(s)
Aborto Inducido , Conducta Anticonceptiva , Recolección de Datos , Escolaridad , Servicios de Planificación Familiar , Estado Civil , Matrimonio , Características de la Población , Población , Historia Reproductiva , Conducta Sexual , Américas , Conducta , Tasa de Natalidad , Brasil , Anticoncepción , Atención a la Salud , Demografía , Países Desarrollados , Países en Desarrollo , Economía , Fertilidad , Planificación en Salud , Accesibilidad a los Servicios de Salud , Administración de los Servicios de Salud , América Latina , Comercialización de los Servicios de Salud , Dinámica Poblacional , Investigación , Muestreo , Clase Social , Factores Socioeconómicos , América del Sur
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