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Efeitos do Triton WR 1339, sulfato de protamina E heparina sobre a lipólise e a remoção plasmática de quilomícrons artificiais em ratos / Effects of Triton WR 1339, protamine sulfate and heparin in the lipolise and plasma removal of artificial quilomicrons in ratsHirata, Mario Hiroyuki 27 December 1985 (has links)
Emulsões artificiais sem proteína simulando quilomicrons e remanescentes de quilomícron foram preparadas por sonicalcação de trioleína, lecitina, colesteril oleato e colesterol em solução aquosa. A seguir foram ultracentrifugadas em gradiente descontínuo de densidade. As emulsões, marcadas com 3H-trioleína e 14C-colesteril oleato foram injetadas via intra-arterial em ratos controle e em ratos tratados com Triton WR1339, sulfato de protamina e heparina, medindo-se a seguir a remoção plasmática do colesteril-ester e dos triglicérides, durante dez minutos. O Triton WR 1339 e a protamina inibiram a lipólise dos quilomícrons artificiais, diminuindo a remoção destas partículas do plasma. O Triton WR 1339 mostrou ser mais efetivo que a protamina nestes efeitos. Por outro lado, a heparina promoveu uma lipólise rápida e brusca nos quilomícrons artificiais, assim como uma aceleração na remoção destas partículas do plasma. Em contraste flagrante com esses resultados, o metabolismo dos remanescentes de quilomícron não foi consideravelmente afetado pelo tratamento com Triton e heparina. Estas experiências indicam que as emulsões artificiais reproduzem o comportamento metabólico dos quilomícrons e remanescentes de quilomícron naturais, em condições em que a atividade da lipase lipoproteica esteja alterada. / Protein-free emulsions models of chylomicrons and chylomicron remnants were prepared by sonicating triolein, lecithin., cholesteryl oleate and cholesterol in aqueous saline media, followed by ultracentrifugation in density gradient solution. The 3H-triolein and 14C-cholesteryl oleate labeled emulsions were injected into the carotid artery of control rats and rats treated with Triton WR 1339, protamine sulphate and heparin. Plasma removal of both labels was measured during ten minutes in two minutes intervals. Triton WR 1339 and protamine sulphate strongly inhibited lipolysis of chylomicron-like emulsions leading to delayed removal of the particles from blood. Triton WR 1339 de appeared to be more effective than protamine to elicit these effects. On the other hand, heparin produced instantaneous lipolysis of the chylomicron-like particles markedly enhancing its removal from plasma. Contrarily, chylomicron remnant-like emulsions were not considerably affected either by Triton WR 1339 or by heparin treatment. The above described results obtained with artificial emulsions support current concepts on the metabolic behavior of natural chylomicron and remnant submitted to changes in lipoprotein lipase action.
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Dietary Fiber/Carnitine, Diacylglycerol, and Low Glycemic Index Starch Effects on Obesity and Triglyceride Rich Lipoprotein Metabolsim in DogsMitsuhashi, Yuka 2009 December 1900 (has links)
Obesity is the most common clinical disorder and is associated with various
medical conditions in dogs. Appropriate dietary management potentially provides weight
loss in a safe, healthy, and efficacious manner. In order to elucidate whether dietary
fiber, carnitine, diacylglycerol (DAG), and low glycemic index (LGI) act on such dietary
components, a series of studies was conducted: 1) the combination of dietary
fiber/carnitine effect on short term (3 and 7 h) satiety and long term (6 weeks) canine
weight loss, 2) the combination of dietary LGI/high glycemic index (HGI) starches and
DAG/triacylglycerol (TAG) effect during a 9 week canine weight loss period, and 3) the
DAG effect on triglyceride rich lipoprotein (TRL) metabolism isolated from canine
plasma 3-4 h postprandially.
The combination of dietary fiber/carnitine supplementation decreased both food
and energy intake at 3 h post-feeding, suggesting that this combination diet provided 3 h
post-meal satiety. This combination supplement also increased postprandial plasma B-
hydroxybutyrate (BHB) at d 42 and body fat and weight loss at d 42 from baseline. This combination supplement did not alter plasma vitamin A distributions or concentrations
although it contained high vitamin A as B-carotene. In the second study, the LGI diets
resulted in a more pronounced body weight loss than the HGI diets due to lower diet
digestibilities. These data are consistent with LGI diets decreasing metabolizable energy
and consequently consuming less energy compared to the HGI diets. The DAG diets
lowered postprandial plasma TAG at weeks 1 and 8 in and increased plasma BHB at
week 8, suggesting an increase in fat oxidation. The combination of DAG/LGI decreased
postprandial total cholesterol at week 8. Lipoprotein concentrations were not altered by
diet types. Fasting lipoprotein lipase (LPL) and hepatic lipase (HL) activities were not
affected by diets. In the final study, DAG ingestion decreased TRL and plasma TAG
concentrations vs. TAG ingestion. The DAG enriched meal increased non-esterified
fatty acid, monoacylglycerol, and 1,3-DAG and decreased TAG in TRLs which may be
attributed to larger TRL particle size compared to the TAG meal. Consequently, the
DAG derived TRLs showed increased affinity of core TAG for LPL and HL in vitro.
Moreover, the intravenous injection of the DAG derived canine TRLs into mice
underwent more rapid blood clearance associated with the greater hepatic uptake
compared to the TAG derived TRL injection.
In conclusion, the combination of dietary fiber/carnitine and DAG/LGI
preferably reduced body weight and stimulated fat oxidation, which promotes overall
weight loss. The postprandial plasma TAG lowering effect of DAG is the result, at least
partially, from the efficient clearance of TRLs from blood circulation and their ability to
act as a more efficient substrate for plasma lipolytic enzymes.
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Efeitos do Triton WR 1339, sulfato de protamina E heparina sobre a lipólise e a remoção plasmática de quilomícrons artificiais em ratos / Effects of Triton WR 1339, protamine sulfate and heparin in the lipolise and plasma removal of artificial quilomicrons in ratsMario Hiroyuki Hirata 27 December 1985 (has links)
Emulsões artificiais sem proteína simulando quilomicrons e remanescentes de quilomícron foram preparadas por sonicalcação de trioleína, lecitina, colesteril oleato e colesterol em solução aquosa. A seguir foram ultracentrifugadas em gradiente descontínuo de densidade. As emulsões, marcadas com 3H-trioleína e 14C-colesteril oleato foram injetadas via intra-arterial em ratos controle e em ratos tratados com Triton WR1339, sulfato de protamina e heparina, medindo-se a seguir a remoção plasmática do colesteril-ester e dos triglicérides, durante dez minutos. O Triton WR 1339 e a protamina inibiram a lipólise dos quilomícrons artificiais, diminuindo a remoção destas partículas do plasma. O Triton WR 1339 mostrou ser mais efetivo que a protamina nestes efeitos. Por outro lado, a heparina promoveu uma lipólise rápida e brusca nos quilomícrons artificiais, assim como uma aceleração na remoção destas partículas do plasma. Em contraste flagrante com esses resultados, o metabolismo dos remanescentes de quilomícron não foi consideravelmente afetado pelo tratamento com Triton e heparina. Estas experiências indicam que as emulsões artificiais reproduzem o comportamento metabólico dos quilomícrons e remanescentes de quilomícron naturais, em condições em que a atividade da lipase lipoproteica esteja alterada. / Protein-free emulsions models of chylomicrons and chylomicron remnants were prepared by sonicating triolein, lecithin., cholesteryl oleate and cholesterol in aqueous saline media, followed by ultracentrifugation in density gradient solution. The 3H-triolein and 14C-cholesteryl oleate labeled emulsions were injected into the carotid artery of control rats and rats treated with Triton WR 1339, protamine sulphate and heparin. Plasma removal of both labels was measured during ten minutes in two minutes intervals. Triton WR 1339 and protamine sulphate strongly inhibited lipolysis of chylomicron-like emulsions leading to delayed removal of the particles from blood. Triton WR 1339 de appeared to be more effective than protamine to elicit these effects. On the other hand, heparin produced instantaneous lipolysis of the chylomicron-like particles markedly enhancing its removal from plasma. Contrarily, chylomicron remnant-like emulsions were not considerably affected either by Triton WR 1339 or by heparin treatment. The above described results obtained with artificial emulsions support current concepts on the metabolic behavior of natural chylomicron and remnant submitted to changes in lipoprotein lipase action.
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