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1.
Arq. bras. med. vet. zootec ; 58(3): 421-426, jun. 2006. tab
Artículo en Portugués | LILACS | ID: lil-443598

RESUMEN

Avaliaram-se 49 marcas de rações para cães adultos e filhotes comercializadas em Jaboticabal-SP. Os alimentos foram divididos em três segmentos: econômico, standard e super-premium. Nessa ordem, as rações para cães adultos apresentaram, em média, 16,9 por cento, 20,9 por cento e 27,8 por cento de proteína, 9,7 por cento, 10,5 por cento e 15 por cento de gordura, 6,4 por cento, 2,9 por cento e 1,1 por cento de fibra e 1,9 por cento, 1,9 por cento e 1,4 por cento de Ca. Para filhotes, os produtos standard e super-premium apresentaram, respectivamente, 26,1 por cento e 31,0 por cento de proteína, 10,8 por cento e 15,2 por cento de gordura, 2,6 por cento e 2,4 por cento de fibra, 2,1 por cento e 1,7 por cento de Ca e 1,6 por cento e 1,3 por cento de P. A porcentagem de rações cujos teores nutricionais declarados no rótulo não estavam de acordo com os encontrados nas análises de laboratório foi, para os produtos super-premium para filhotes, 80,0 por cento para o Ca e 60,0 por cento para a gordura; para os produtos standard para filhotes, 28,6 por cento para proteína e 57,2 por cento para o cálcio; para os produtos econômicos para cães adultos, 44,0 por cento para a fibra e 33,0 por cento para a proteína; para os produtos standard para cães adultos de 33,0 por cento para a gordura e 50,0 por cento para o Ca; e para os produtos super-premium para cães adultos, 50,0 por cento para o cálcio e 33,0 por cento para a gordura. Foram encontradas inadequações nutricionais em produtos, como teores insuficientes de proteína e altas concentrações de fibra, cálcio e fósforo.


Fortynine food products for adult or juvenile dogs, commercially available in Jaboticabal, São Paulo, Brazil, were tested for nutrient composition. The products were divided into three categories: low-cost, standard and super-premium. In that order, average compositions for adult foods were 16.9 percent, 20.9 percent and 27.8 percent protein, 9.7 percent, 10.5 percent and 15 percent fat, 6.4 percent, 2.9 percent and 1.1 percent fiber, and 1.9 percent, 1.9 percent and 1.4 percent calcium. For puppy foods, the average compositions of standard and super-premium foods were 26.1 percent and 31 percent protein, 10.8 percent and 15.2 percent fat, 2.6 percent and 2.4 percent fiber, 2.1 percent and 1.7 percent Ca, and 1.6 percent and 1.3 percent P, respectively. The percentages of products whose published label values were in disagreement with laboratory results were: super-premium products for puppies, 80 percent for Ca and 60 percent for fat; standard products for puppies, 28.6 percent for protein and 57.2 percent for Ca; low-cost products for adults, 44 percent for fiber and 33 percent for protein; standard products for adults, 33 percent for fat and 50 percent for Ca; super-premium products for adults, 50 percent for calcium and 33 percent for fat. Products with nutritional shortcomings were found, such as insufficient protein content and too high levels of fiber, calcium, and phosphorus.


Asunto(s)
Perros , Composición de Alimentos , Alimentación Animal/análisis
2.
J Vasc Interv Radiol ; 10(9): 1149-57, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10527190

RESUMEN

PURPOSE: To evaluate the safety and short-term efficacy of uterine fibroid embolization (UFE) in patients with symptomatic uterine fibroids. MATERIALS AND METHODS: Bilateral UFE was performed in 61 patients with symptomatic uterine leiomyomata during a 16-month period. Imaging was performed before the procedure and at 3 months and 1 year after the procedure. Questionnaires were obtained at regular intervals after the procedure to assess patient outcome. RESULTS: All procedures but one were technically successful. Mean clinical follow-up was 8.7 months. Minor complications occurred in five patients during the follow-up period. All were treated without permanent sequelae. Menstrual bleeding was improved in 89%, with 81% of patients moderately to markedly improved. Pelvic pain and pressure was improved in 96% of patients, with moderate to marked improvement in 79%. At initial imaging follow-up (mean, 4.4 months postprocedure), median uterine volume decreased 34% (P = .0001) and the median dominant fibroid volume decreased 50% (P = .0001). Imaging at 1 year (mean, 12.3 months) after the procedure showed continued reduction with a median uterine volume reduction of 48% (P = .0002) and median dominant fibroid volume decrease of 78% (P = .0002). CONCLUSION: In the authors' initial clinical experience, UFE appears effective in controlling symptoms and substantially reducing fibroid volume with few complications.


Asunto(s)
Embolización Terapéutica/métodos , Leiomioma/terapia , Neoplasias Uterinas/terapia , Adulto , Angiografía de Substracción Digital , Arterias , Estudios de Evaluación como Asunto , Femenino , Humanos , Leiomioma/irrigación sanguínea , Tiempo de Internación/estadística & datos numéricos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Satisfacción del Paciente , Complicaciones Posoperatorias , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Resultado del Tratamiento , Neoplasias Uterinas/irrigación sanguínea , Útero/irrigación sanguínea
3.
Braz J Med Biol Res ; 32(10): 1269-76, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10510265

RESUMEN

Policosanol is a mixture of higher aliphatic primary alcohols isolated from sugar cane wax, whose main component is octacosanol. An inhibitory effect of policosanol on platelet aggregation and cerebral ischemia in animal models has been reported. Thus, the objective of the present study was to evaluate the effect of policosanol on cerebral ischemia induced by unilateral carotid ligation and bilateral clamping and recirculation in Mongolian gerbils. Policosanol (200 mg/kg) administered immediately after unilateral carotid ligation and at 12- or 24-h intervals for 48 h significantly inhibited mortality and clinical symptoms when compared with controls, whereas lower doses (100 mg/kg) were not effective. Control animals showed swelling (tissue vacuolization) and necrosis of neurons in all areas of the brain studied (frontal cortex, hippocampus, striatum and olfactory tubercle), showing a similar injury profile. In the group treated with 200 mg/kg policosanol swelling and necrosis were significantly reduced when compared with the control group. In another experimental model, comparison between groups showed that the brain water content of control gerbils (N = 15) was significantly higher after 15 min of clamping and 4 h of recirculation than in sham-operated animals (N = 13), whereas policosanol (200 mg/kg) (N = 19) significantly reduced the edema compared with the control group, with a cerebral water content identical to that of the sham-operated animals. cAMP levels in the brain of control-ligated Mongolian gerbils (N = 8) were significantly lower than those of sham-operated animals (N = 10). The policosanol-treated group (N = 10) showed significantly higher cAMP levels (2.68 pmol/g of tissue) than the positive control (1.91 pmol/g of tissue) and similar to those of non-ligated gerbils (2.97 pmol/g of tissue). In conclusion, our results show an anti-ischemic effect of policosanol administered after induction of cerebral ischemia, in two different experimental models in Mongolian gerbils, suggesting a possible therapeutic effect in cerebral vascular disorders.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , AMP Cíclico/análisis , Alcoholes Grasos/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Animales , Isquemia Encefálica/patología , Constricción , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Femenino , Gerbillinae
4.
Braz. j. med. biol. res ; 32(10): 1269-76, Oct. 1999. tab
Artículo en Inglés | LILACS | ID: lil-252278

RESUMEN

Policosanol is a mixture of higher aliphatic primary alcohols isolated from sugar cane wax, whose main component is octacosanol. An inhibitory effect of policosanol on platelet aggregation and cerebral ischemia in animal models has been reported. Thus, the objective of the present study was to evaluate the effect of policosanol on cerebral ischemia induced by unilateral carotid ligation and bilateral clamping and recirculation in Mongolian gerbils. Policosanol (200 mg/kg) administered immediately after unilateral carotid ligation and at 12- or 24-h intervals for 48 h significantly inhibited mortality and clinical symptoms when compared with controls, whereas lower doses (100 mg/kg) were not effective. Control animals showed swelling (tissue vacuolization) and necrosis of neurons in all areas of the brain studied (frontal cortex, hippocampus, striatum and olfactory tubercle), showing a similar injury profile. In the group treated with 200 mg/kg policosanol swelling and necrosis were significantly reduced when compared with the control group. In another experimental model, comparison between groups showed that the brain water content of control gerbils (N = 15) was significantly higher after 15 min of clamping and 4 h of recirculation than in sham-operated animals (N = 13), whereas policosanol (200 mg/kg) (N = 19) significantly reduced the edema compared with the control group, with a cerebral water content identical to that of the sham-operated animals. cAMP levels in the brain of control-ligated Mongolian gerbils (N = 8) were significantly lower than those of sham-operated animals (N = 10). The policosanol-treated group (N = 10) showed significantly higher cAMP levels (2.68 pmol/g of tissue) than the positive control (1.91 pmol/g of tissue) and similar to those of non-ligated gerbils (2.97 pmol/g of tissue). In conclusion, our results show an anti-ischemic effect of policosanol administered after induction of cerebral ischemia, in two different experimental models in Mongolian gerbils, suggesting a possible therapeutic effect in cerebral vascular disorders


Asunto(s)
Animales , Femenino , Isquemia Encefálica/terapia , AMP Cíclico/análisis , Alcoholes Grasos/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Isquemia Encefálica/patología , Constricción , Modelos Animales de Enfermedad , Gerbillinae
5.
Physiol Behav ; 67(1): 1-7, 1999 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-10463622

RESUMEN

Policosanol, a new cholesterol-lowering agent, is a mixture of higher aliphatic primary alcohols isolated from sugar cane (Saccharum officinarum L.) wax, which prevents the onset of espontaneously and experimentally induced atherosclerotic lesions in experimental models. Because the oxidation of low-density lipoprotein (LDL) may play a role in the pathogenesis of atherosclerosis, we investigate the effect of policosanol on copper oxidative susceptibility of rat lipoprotein fractions (VLDL + LDL). Rats fed normal diet were treated with policosanol (250-500 mg/kg/day) for up to 4 weeks. EDTA-free lipoprotein particles were oxidized in a cell-free system by the addition of copper ions, and conjugated dienes generation was monitored by changes of optical density at 234 nm. Thiobarbituric acid-reactive substances (TBARS) content and lysine-amino group reactivity were investigated. After administration, there was no change in cholesterol, triglycerides, and phospholipid content of lipoprotein fractions; however, policosanol significantly prolongs the lag time and reduces the propagation rate of diene generation. Also, policosanol reduces TBARS content and increases lysine reactivity in lipoprotein fractions treated with Cu2+. In conclusion, policosanol, in addition to its cholesterol-lowering effect, has other properties that enables it to reduce the potential of lipoprotein to undergo lipid peroxidation. Such effect can be considered of promissory value in the management of atherosclerosis.


Asunto(s)
Anticolesterolemiantes/farmacología , Cobre/farmacología , Alcoholes Grasos/farmacología , Peroxidación de Lípido/efectos de los fármacos , Lipoproteínas LDL/efectos de los fármacos , Lipoproteínas VLDL/efectos de los fármacos , Animales , Arteriosclerosis/metabolismo , Lipoproteínas LDL/metabolismo , Lipoproteínas VLDL/metabolismo , Lisina/metabolismo , Masculino , Oxidación-Reducción , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
6.
Arch Med Res ; 28(3): 355-60, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9291630

RESUMEN

Policosanol, a defined mixture of high molecular weight aliphatic alcohol isolated and purified from sugar cane (Saccharum officinarum, L) wax is a new cholesterol-lowering agent effective in experimental models, healthy volunteers, and patients with type II hypercholesterolemia. Also, policosanol prevents the onset of spontaneously- and experimentally-induced atherosclerotic lesions and cerebral ischemia in Mongolian gerbils. Free radicals are linked to many diseases including atherosclerosis and ischemia/ reoxidation cellular injury. Therefore, in this study the authors evaluate the antioxidant activity of policosanol on rat liver microsomes. The extent of lipid peroxidation was measured by thiobarbituric acid reactive substances (TBARS). When policosanol was administered orally (100 and 250 mg/kg) for up to 4 weeks, a partial prevention of rat in vitro microsomal lipid peroxidation was noted. The formation of TBARS in microsomes isolated from treated rats was significantly decreased by about 50%, when peroxidation was initiated by Fe3+/ADP/ NADPH, Fe2+/ascorbate and CCl4/NADPH-generating system. Also, oral administration of policosanol in rats provides a partial inhibition of lipid peroxidation, but the mechanism supporting such effect remains to be elucidated. This beneficial effect of policosanol on membrane lipid peroxidation may be useful in protecting to some extent against free radical-associated diseases.


Asunto(s)
Anticolesterolemiantes/farmacología , Antioxidantes/farmacología , Alcoholes Grasos/farmacología , Peroxidación de Lípido/efectos de los fármacos , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Animales , Masculino , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
7.
Br J Nutr ; 77(6): 923-32, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9227189

RESUMEN

The effect of policosanol, a mixture of high-molecular-weight aliphatic alcohols isolated from sugarcane wax, on casein-induced hypercholesterolaemia in rabbits was studied. When policosanol was administered by the oral route once daily for 30 d (50 mg/kg) the increases in plasma total cholesterol and LDL-cholesterol (LDC-C) were significantly reduced when compared with the control group. The incorporation of 3H2O into sterols in the liver was significantly depressed, suggesting inhibition of hepatic cholesterol biosynthesis. The oral administration of policosanol raised the rate of removal of 125I-labelled LDL from serum. Kinetic parameters calculated following injection of [125I]LDL showed than in casein-fed rabbits, the terminal half-life (t1/2) was significantly decreased after policosanol treatment. The hepatic LDL-binding activity was increased after policosanol administration which suggested that the enhanced clearance was due, at least in part, to increased receptor-mediated uptake of LDL by the liver. Considered together, these results suggest that policosanol can significantly reduce the increase of plasma LDL-C in rabbits fed on a wheat starch-casein diet by reducing cholesterol biosynthesis in the liver. Such an effect could account for the enhancement of LDL catabolism through the receptor-mediated pathway.


Asunto(s)
Anticolesterolemiantes/farmacología , Alcoholes Grasos/farmacología , Hipercolesterolemia/tratamiento farmacológico , Animales , Caseínas , Colesterol/biosíntesis , LDL-Colesterol/sangre , LDL-Colesterol/metabolismo , Radioisótopos de Yodo , Hígado/metabolismo , Masculino , Unión Proteica/efectos de los fármacos , Conejos , Receptores de LDL/metabolismo , Triticum
8.
Biol Res ; 29(2): 253-7, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9278716

RESUMEN

We have suggested previously, measuring 14C-acetate incorporation into free cholesterol, that oral administration of policosanol inhibits hepatic cholesterol biosynthesis in rats. Nevertheless, since acetate has limitations to study cholesterol synthesis in vivo, we now investigate rates of incorporation of labeled water into hepatic sterol after policosanol treatment. Absolute rates of incorporation of 3H-water in sterols were depressed by policosanol by about 20%, giving a more accurate degree of cholesterol biosynthesis inhibition in this species. Since policosanol did not inhibit labeled mevalonate incorporation into cholesterol in rat liver, we also studied the effect of policosanol on hydroxy-methylglutaryl-coenzyme A (HMG-CoA) reductase. Reductase activity assayed in microsomes treated with policosanol remained unchanged, suggesting that cholesterol synthesis is not inhibited by a direct action of policosanol on this enzyme.


Asunto(s)
Anticolesterolemiantes/farmacología , Colesterol/biosíntesis , Alcoholes Grasos/farmacología , Hidroximetilglutaril-CoA Reductasas/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Microsomas/efectos de los fármacos , Animales , Masculino , Ratas , Ratas Wistar
9.
Biol. Res ; 29(2): 253-7, 1996.
Artículo en Inglés | LILACS | ID: lil-228539

RESUMEN

We have suggested previously, measuring 14C-acetate incorporation into free cholesterol, that oral administration of policosanol inhibits hepatic cholesterol biosynthesis in rats. Nevertheless, since acetate has limitations to study cholesterol synthesis in vivo, we now investigate rates of incorporation of labeled water into hepatic sterol after policosanol treatment. Absolute rates of incorporation of 3H-water in sterols were depressed by policosanol by about 20 percent, giving a more accurate degree of cholesterol biosynthesis inhibition in this species. Since policosanol did not inhibit labeled mevalonate incorporation into cholesterol in rat liver, we also studied the effect of policosanol on hydroxy-methylglutaryl-coenzyme A (HMG-CoA) reductase. Reductase activity assayed in microsomes treated with policosanol remained unchanged, suggesting that cholesterol synthesis is not inhibited by a direct action of policosanol on this enzyme


Asunto(s)
Animales , Masculino , Ratas , Anticolesterolemiantes/farmacología , Colesterol/biosíntesis , Alcoholes Grasos/farmacología , Hidroximetilglutaril-CoA Reductasas/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Microsomas/efectos de los fármacos , Ratas Wistar
10.
Food Chem Toxicol ; 32(6): 565-75, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8045464

RESUMEN

Policosanol, administered orally, has shown a cholesterol-lowering effect in different experimental models. Because lipid-lowering therapy is administered chronically, it is necessary to know the effects of these drugs after long-term administration. 18 adult male Macaca arctoides monkeys were used to study the cholesterol-lowering effects and possible toxicity produced by oral administration of policosanol (0.25, 2.5 and 25 mg/kg) for 54 wk. After 8 wk, a significant reduction of serum total cholesterol and low-density lipoprotein cholesterol was observed in policosanol-treated animals when compared with the controls; this effect persisted throughout the study. The animals' behavioural repertoire, physical condition, haematology and blood biochemistry, as well as spermiogram analysis and electrocardiography, were monitored during the study; ophthalmological and pathological anatomy examinations were performed at the end of the administration period. No drug-related toxicity was detected by any examination. The results gave further evidence of the marked and persistent cholesterol-lowering effects of policosanol that had been observed in different experimental models. There was a significant reduction of spontaneous aortic atherosclerotic lesions in treated animals compared with controls. Policosanol (0.25-25 mg/kg) administered orally for 54 wk brought about a persistent reduction in blood cholesterol levels and was very safe and well tolerated during long-term administration.


Asunto(s)
LDL-Colesterol/sangre , Colesterol/sangre , Alcoholes Grasos/farmacología , Administración Oral , Animales , Aorta/efectos de los fármacos , Arteriosclerosis/prevención & control , Conducta Animal/efectos de los fármacos , HDL-Colesterol/sangre , Electrocardiografía/efectos de los fármacos , Ojo/efectos de los fármacos , Alcoholes Grasos/administración & dosificación , Alcoholes Grasos/toxicidad , Macaca , Masculino , Espermatogénesis/efectos de los fármacos
11.
Toxicol Lett ; 70(1): 77-87, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8310460

RESUMEN

Policosanol is a natural mixture of higher aliphatic primary alcohols. Oral toxicity of policosanol was evaluated in a 12-month study in which doses from 0.5 to 500 mg/kg were given orally to Sprague Dawley (SD) rats (20/sex/group) daily. There was no treatment-related toxicity. Thus, effects on body weight gain, food consumption, clinical observations, blood biochemistry, hematology, organ weight ratios and histopathological findings were similar in control and treated groups. This study supports the wide safety margin of policosanol when administered chronically.


Asunto(s)
Alcoholes Grasos/toxicidad , Inhibidores de Agregación Plaquetaria/toxicidad , Administración Oral , Análisis de Varianza , Animales , Biomarcadores/sangre , Análisis Químico de la Sangre , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Alcoholes Grasos/administración & dosificación , Femenino , Hígado/efectos de los fármacos , Hígado/ultraestructura , Masculino , Tamaño de los Órganos/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/administración & dosificación , Ratas , Ratas Sprague-Dawley
12.
Biol Res ; 27(3-4): 199-203, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8728831

RESUMEN

Policosanol is a mixture of aliphatic primary alcohols isolated and purified from sugar cane wax, that induces cholesterol-lowering effects in experimental models and human beings. When human lung fibroblasts were incubated with policosanol for 48 hours prior to the experiment, a dose dependent inhibition of 14C-acetate incorporation into total cholesterol was observed, whereas labeled mevalonate incorporation was not inhibited. Even when cholesterol synthesis was not strongly inhibited, low density lipoprotein (LDL) processing was markedly enhanced. Thus, LDL binding, internalization and degradation were significantly increased after policosanol treatment. In addition, despite the fact that'cholesterol generation was not inhibited at the lowest dose of policosanol assayed, LDL processing was significantly increased. The current data indicate that policosanol inhibits cholesterol synthesis at the earliest steps of the cholesterol biosynthetic pathway. On the other hand, this study suggests that the increase in LDL processing may be partially explained by the inhibition of cholesterol biosynthesis, even though an sterol-independent mechanism might be responsible for the enhancement of LDL-receptor activity.


Asunto(s)
Anticolesterolemiantes/farmacología , Colesterol/biosíntesis , Alcoholes Grasos/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Lipoproteínas LDL/metabolismo , Células Cultivadas , Humanos
13.
Biol. Res ; 27(3/4): 199-203, 1994. tab
Artículo en Inglés | CUMED | ID: cum-43915

RESUMEN

Policosanol is a mixture of aliphatic primary alcohols isolated and purified from sugar cane wax, that induces cholesterol-lowering effects in experimental models and human beings. When human lung fibroblasts were incubated with policosanol for 48 hours prior to the experiment, a dose dependent inhibition of 14C-acetate incorporation into total cholesterol was observed, whereas labeled mevalonate incorporation was not inhibited. Even when cholesterol synthesis was not strongly inhibited, low density lipoprotein (LDL) processing was markedly enhanced. Thus, LDL binding, internalization and degradation were significantly increased after policosanol treatment. In addition, despite the fact that'cholesterol generation was not inhibited at the lowest dose of policosanol assayed, LDL processing was significantly increased. The current data indicate that policosanol inhibits cholesterol synthesis at the earliest steps of the cholesterol biosynthetic pathway. On the other hand, this study suggests that the increase in LDL processing may be partially explained by the inhibition of cholesterol biosynthesis, even though an sterol-independent mechanism might be responsible for the enhancement of LDL-receptor activity(AU)


Asunto(s)
Humanos , Anticolesterolemiantes/farmacología , Colesterol/biosíntesis , Alcoholes Grasos/farmacología , Fibroblastos , Fibroblastos/metabolismo , Lipoproteínas LDL/metabolismo , Células Cultivadas
14.
Biol. Res ; 27(3/4): 199-203, 1994. tab
Artículo en Inglés | LILACS | ID: lil-228579

RESUMEN

Policosanol is a mixture of aliphatic primary alcohols isolated and purified from sugar cane wax, that induces cholesterol-lowering effects in experimental models and human beings. When human lung fibroblasts were incubated with policosanol for 48 hours prior to the experiment, a dose dependent inhibition of 14C-acetate incorporation into total cholesterol was observed, whereas labeled mevalonate incorporation was not inhibited. Even when cholesterol synthesis was not strongly inhibited, low density lipoprotein (LDL) processing was markedly enhanced. Thus, LDL binding, internalization and degradation were significantly increased after policosanol treatment. In addition, despite the fact that'cholesterol generation was not inhibited at the lowest dose of policosanol assayed, LDL processing was significantly increased. The current data indicate that policosanol inhibits cholesterol synthesis at the earliest steps of the cholesterol biosynthetic pathway. On the other hand, this study suggests that the increase in LDL processing may be partially explained by the inhibition of cholesterol biosynthesis, even though an sterol-independent mechanism might be responsible for the enhancement of LDL-receptor activity


Asunto(s)
Humanos , Anticolesterolemiantes/farmacología , Colesterol/biosíntesis , Alcoholes Grasos/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Lipoproteínas LDL/metabolismo , Células Cultivadas
15.
Thromb Res ; 69(3): 321-7, 1993 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-8475481

RESUMEN

Policosanol is the trivial name of a mixture of high molecular weight alcohols isolated from sugar cane, wherein octacosanol is the main component. The effects of Policosanol treatment on rat platelet aggregation were studied. Depending on the dose, Policosanol (5-20 mg/kg, perorally) inhibited the decrease in circulating platelet counts and collagen-induced malondialdehyde concentration in plasma. In rat clotted whole blood thromboxane B2 formation was inhibited by Policosanol (25 mg/kg). Policosanol (50-200 mg/kg, single doses) inhibited ADP-induced platelet aggregation in platelet-rich plasma, while lower doses (25 mg/kg) did not change responses to ADP significantly. However, rats treated with this dose (25 mg/kg) for 4 weeks showed a significant inhibition of platelet aggregation in PRP when a submaximal ADP concentrations was administered.


Asunto(s)
Alcoholes Grasos/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Adenosina Difosfato/antagonistas & inhibidores , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Sprague-Dawley , Tromboxano B2/sangre
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