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2P-0549 OT-13540: Novel compound has several antiatherogenic effects
Tuesday September 30, 2003: Poster Session Therapy
160
THERAPY 2P-0548
Metalloproteinase inhibitor can modulate the synthesis of intimal hyperplasia induced in hyper lipidemic rabbit
Y. Okamoto 1 , K. Satomura 2 , F. Osuzu 2 , M. Yoshioka 2 , H. Nakamura 3 . 1 JSDF Central Hospital Tokyo; 2 National Defense Medical College; 3 Mitsukoshi Health and Welfare Foundation, Japan Objectives: Inhibition of metalloproteinases (MMPs) is proved to reduce vascular remodeling. However, this inhibition is not clear to modulate the synthesis of atherosclerotic intimal hyperplasia. Animal experiments were conducted whether broad-spectrum MMPs inhibitor (MMPi, ONO-4817) can modulate the synthesis of newly induced intimal hyperplasia in hyperlipidemic rabbit. Methods: Three rabbits were fed with laboratory chow with 1%cholesterol without any other stimulation for 3months (Chol). After 2 months fed with 1%cholesterol, three rabbits were orally administered 100mg/kg-BW ONO4817 with continuing 1%cholesterol feedings for 1month (ONO). After these procedures, abdominal aortas of the rabbits were studied with histochemical methods. Results: Formation of intimal hyperplasia was inhibited in ONO. Distribution of macrophage in the hyperplasia of ONO was different from that in the hyperplasia of Chol. Destruction of internal elastic lamina was not observed in the intimal hyperplasia of ONO.
2P-0550
Possible mechanisms for the antiobesity effects of a novel compound OT-13540
Y. Inoue, A. Hagi, S. Miki, N. Yoshinaga, M. Doi, K. Doi, K. Miyata. Otsuka Pharmaceutical Factory, Inc., Japan Objectives: We have developed a novel compound, OT-13540 (OT), which has antiatherogenic effects in rats with experimental atherosclerosis. Administration of OT also significantly reduced body weight gain in normal rats. In this study, we examined the possible mechanisms for the antiobesity effects of OT in normal rats. Methods: Normal rats received OT or vehicle alone by oral gavage. Serum cholesterol (TC), triglyceride (TG), and HDL cholesterol (HDL-C) levels were determined. We used Caco-2 cells to determine acyl CoA:diacylglycerol acyltransferase (DGAT) activity. Lipoprotein lipase (LPL) activity in post-heparin plasma was measured by an immunochemical method. Results: Administration of OT (100 mg/kg) for 14 days significantly increased serum HDL-C (77% compared with controls, p< 0.01), and significantly reduced body weight gain (11% compared with controls, p< 0.05). Food consumption and organ weights were unchanged after administration of OT. OT inhibited DGAT activity (IC50 = 11.63 microgram/ml; the plasma OT concentration in rats was 18.8±1.2 microgram/ml following single oral administration of OT at a dose of 100 mg/kg), and significantly increased LPL activity in post-heparin plasma (28% compared with control, p< 0.01). Conclusions: One of the key enzymes in triglyceride synthesis is DGAT, which catalyzes the final step in mammalian triglyceride synthesis. LPL is of major importance in lipid metabolism. Mice that are DGAT-deficient and mice that overexpress LPL in muscle are resistant to obesity. The results of this study indicate that the antiobesity effect of OT may be caused by the dual effect of DGAT inhibition and lipoprotein lipase activation. 2P-0551
First in vivo application of a novel extracorporeal plasma delipidation procedure in hyperlipidemic healthy subjects
K. Kostner. Dept. of Cardiology, Univ. of Qeensland, PA-Hospital, Brisbane, Qld., Australia Conclusion: MMPi can modulate the synthesis of intimal hyperplaisa in hyperlipidemic rabbits by changing the distribution of macrophages. Also, MMPi inhibited the destruction of internal elastic lamina. 2P-0549
OT-13540: Novel compound has several antiatherogenic effects
A. Hagi, Y. Inoue, K. Miyata. Otsuka Pharmaceutical Factory, Inc., Japan Objectives: We have discovered a novel compound, OT-13540 (OT), diethyl 4-((4-(4-chlorophenyl)-5-methylthiazol-2-yl)carbamoyl)benzylphosphonate, which has an anti-foam cell formation effect against acetyl LDL-stimulated THP-1 macrophages (IC50 = 0.91 microg/ml). In this study, characterization of OT as an anti-atherogenic drug was examined. Method: In vitro: HepG2 cells were incubated in medium with or without OT for 24 h. Amounts of secreted bile acid, cell surface LDL receptors, and secreted apoB were measured. In vivo: Atherosclerotic lesions were induced in rat carotid arteries by balloon de-endothelialization and hyperlipidemia. The animals were fed an atherogenic diet (2% cholesterol) for 14 days and received either 100 mg/kg of OT or vehicle alone (control) by oral gavage. Serum lipid levels were determined and histological analysis of carotid arteries was conducted. Results: In vitro: OT stimulated bile acid secretion and LDL receptor expression. OT also inhibited secretion of apoB from HepG2 cells (IC50 = 0.30 µg/ml). In vivo: Administration of OT reduced both serum cholesterol (TC) and triglyceride (TG) levels (28% and 51% vs. control, respectively) and increased serum HDL-C levels (36% vs. control). The number of intimal lipid droplets and macrophages in carotid arteries were significantly reduced compared with controls (p < 0.0081 and p < 0.0267, respectively). Conclusion: These data indicate that OT may directly prevent the development of plaque lesions (not by an ACAT inhibitory effect) and shift the plasma to an anti-atherosclerotic profile by decreasing LDL-C and TG concentrations and increasing of HDL-C concentration. Further study of OT’s molecular target is necessary.
Objectives: We recently developed a Plasma Delipidation Process (PDP), a novel extracorporeal solvent extraction procedure that removes virtually all cholesterol and triglyceride from treated plasma while not affecting important blood constituents including apolipoproteins. PDP has been shown to be safe in several animal models including roosters, pigs, calves and dogs. We could also show regression of induced atherosclerosis in several animal models. Here we report the first treatment of human volunteers in a phase I clinical trial with PDP. Methods: Plasma was separated via plasmapheresis, delipidated with organic solvents and reinfused into healthy hyperlipidemic volunteers. Results: Virtually 100% of cholesterol and triglycerides, but only 40% of phospholipids were removed from the subjects plasma before reinfusion. Apolipoproteins AI, AII, E, CII, CIII, B and Lp(a) were virtually unchanged in the delipidated plasma. All these apolipoproteins plus Chol, TG and PL in the different lipoprotein fractions were also analysed after reinfusion of the delipidated plasma in a time kinetic study. Conclusion: Cholesterol and triglycerides can be reduced by virtually 100% in plasma of hyperlipidemic patients without significantly affecting apolipoproteins with this new plasma delipidation procedure. 2P-0552
Pitavastatin induces plaque stabilization in Watanabe heritable hyperlipidemic rabbits
H. Kobayashi 1 , H. Suzuki 1 , F. Sato 1 , Y. Yonemitsu 2 , Y. Nakashima 2 , K. Sueishi 2 . 1 Kowa Company, Ltd., Tokyo; 2 Kyushu University, Japan Objective: To investigate the effect of pitavastatin, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor with a strong cholesterollowering activity, on plaque stabilization in Watanabe heritable hyperlipidemic (WHHL) rabbits. Methods: Twenty-two male WHHL rabbits aged 3 months were divided into two groups, a control group and a pitavastatin group. Pitavastatin was administered to WHHL rabbits in drinking water (0.5mg equivalent/kg/day) for 16 weeks. The plaque stabilization was assessed by immunohistochemistry. Results: Pitavastatin significantly reduced the plasma total cholesterol (TC), very low density lipoprotein (VLDL)-C, intermediate density lipoprotein (IDL)-C and low density lipoprotein (LDL)-C (28.6, 60.0, 42.3 and 21.7%, respectively). In the aorta, pitavastatin reduced the surface lesion area (38.6%). In the histopathological study, pitavastatin decreased the percent area
XIIIth International Symposium on Atherosclerosis, September 28–October 2, 2003, Kyoto, Japan
160
THERAPY 2P-0548
Metalloproteinase inhibitor can modulate the synthesis of intimal hyperplasia induced in hyper lipidemic rabbit
Y. Okamoto 1 , K. Satomura 2 , F. Osuzu 2 , M. Yoshioka 2 , H. Nakamura 3 . 1 JSDF Central Hospital Tokyo; 2 National Defense Medical College; 3 Mitsukoshi Health and Welfare Foundation, Japan Objectives: Inhibition of metalloproteinases (MMPs) is proved to reduce vascular remodeling. However, this inhibition is not clear to modulate the synthesis of atherosclerotic intimal hyperplasia. Animal experiments were conducted whether broad-spectrum MMPs inhibitor (MMPi, ONO-4817) can modulate the synthesis of newly induced intimal hyperplasia in hyperlipidemic rabbit. Methods: Three rabbits were fed with laboratory chow with 1%cholesterol without any other stimulation for 3months (Chol). After 2 months fed with 1%cholesterol, three rabbits were orally administered 100mg/kg-BW ONO4817 with continuing 1%cholesterol feedings for 1month (ONO). After these procedures, abdominal aortas of the rabbits were studied with histochemical methods. Results: Formation of intimal hyperplasia was inhibited in ONO. Distribution of macrophage in the hyperplasia of ONO was different from that in the hyperplasia of Chol. Destruction of internal elastic lamina was not observed in the intimal hyperplasia of ONO.
2P-0550
Possible mechanisms for the antiobesity effects of a novel compound OT-13540
Y. Inoue, A. Hagi, S. Miki, N. Yoshinaga, M. Doi, K. Doi, K. Miyata. Otsuka Pharmaceutical Factory, Inc., Japan Objectives: We have developed a novel compound, OT-13540 (OT), which has antiatherogenic effects in rats with experimental atherosclerosis. Administration of OT also significantly reduced body weight gain in normal rats. In this study, we examined the possible mechanisms for the antiobesity effects of OT in normal rats. Methods: Normal rats received OT or vehicle alone by oral gavage. Serum cholesterol (TC), triglyceride (TG), and HDL cholesterol (HDL-C) levels were determined. We used Caco-2 cells to determine acyl CoA:diacylglycerol acyltransferase (DGAT) activity. Lipoprotein lipase (LPL) activity in post-heparin plasma was measured by an immunochemical method. Results: Administration of OT (100 mg/kg) for 14 days significantly increased serum HDL-C (77% compared with controls, p< 0.01), and significantly reduced body weight gain (11% compared with controls, p< 0.05). Food consumption and organ weights were unchanged after administration of OT. OT inhibited DGAT activity (IC50 = 11.63 microgram/ml; the plasma OT concentration in rats was 18.8±1.2 microgram/ml following single oral administration of OT at a dose of 100 mg/kg), and significantly increased LPL activity in post-heparin plasma (28% compared with control, p< 0.01). Conclusions: One of the key enzymes in triglyceride synthesis is DGAT, which catalyzes the final step in mammalian triglyceride synthesis. LPL is of major importance in lipid metabolism. Mice that are DGAT-deficient and mice that overexpress LPL in muscle are resistant to obesity. The results of this study indicate that the antiobesity effect of OT may be caused by the dual effect of DGAT inhibition and lipoprotein lipase activation. 2P-0551
First in vivo application of a novel extracorporeal plasma delipidation procedure in hyperlipidemic healthy subjects
K. Kostner. Dept. of Cardiology, Univ. of Qeensland, PA-Hospital, Brisbane, Qld., Australia Conclusion: MMPi can modulate the synthesis of intimal hyperplaisa in hyperlipidemic rabbits by changing the distribution of macrophages. Also, MMPi inhibited the destruction of internal elastic lamina. 2P-0549
OT-13540: Novel compound has several antiatherogenic effects
A. Hagi, Y. Inoue, K. Miyata. Otsuka Pharmaceutical Factory, Inc., Japan Objectives: We have discovered a novel compound, OT-13540 (OT), diethyl 4-((4-(4-chlorophenyl)-5-methylthiazol-2-yl)carbamoyl)benzylphosphonate, which has an anti-foam cell formation effect against acetyl LDL-stimulated THP-1 macrophages (IC50 = 0.91 microg/ml). In this study, characterization of OT as an anti-atherogenic drug was examined. Method: In vitro: HepG2 cells were incubated in medium with or without OT for 24 h. Amounts of secreted bile acid, cell surface LDL receptors, and secreted apoB were measured. In vivo: Atherosclerotic lesions were induced in rat carotid arteries by balloon de-endothelialization and hyperlipidemia. The animals were fed an atherogenic diet (2% cholesterol) for 14 days and received either 100 mg/kg of OT or vehicle alone (control) by oral gavage. Serum lipid levels were determined and histological analysis of carotid arteries was conducted. Results: In vitro: OT stimulated bile acid secretion and LDL receptor expression. OT also inhibited secretion of apoB from HepG2 cells (IC50 = 0.30 µg/ml). In vivo: Administration of OT reduced both serum cholesterol (TC) and triglyceride (TG) levels (28% and 51% vs. control, respectively) and increased serum HDL-C levels (36% vs. control). The number of intimal lipid droplets and macrophages in carotid arteries were significantly reduced compared with controls (p < 0.0081 and p < 0.0267, respectively). Conclusion: These data indicate that OT may directly prevent the development of plaque lesions (not by an ACAT inhibitory effect) and shift the plasma to an anti-atherosclerotic profile by decreasing LDL-C and TG concentrations and increasing of HDL-C concentration. Further study of OT’s molecular target is necessary.
Objectives: We recently developed a Plasma Delipidation Process (PDP), a novel extracorporeal solvent extraction procedure that removes virtually all cholesterol and triglyceride from treated plasma while not affecting important blood constituents including apolipoproteins. PDP has been shown to be safe in several animal models including roosters, pigs, calves and dogs. We could also show regression of induced atherosclerosis in several animal models. Here we report the first treatment of human volunteers in a phase I clinical trial with PDP. Methods: Plasma was separated via plasmapheresis, delipidated with organic solvents and reinfused into healthy hyperlipidemic volunteers. Results: Virtually 100% of cholesterol and triglycerides, but only 40% of phospholipids were removed from the subjects plasma before reinfusion. Apolipoproteins AI, AII, E, CII, CIII, B and Lp(a) were virtually unchanged in the delipidated plasma. All these apolipoproteins plus Chol, TG and PL in the different lipoprotein fractions were also analysed after reinfusion of the delipidated plasma in a time kinetic study. Conclusion: Cholesterol and triglycerides can be reduced by virtually 100% in plasma of hyperlipidemic patients without significantly affecting apolipoproteins with this new plasma delipidation procedure. 2P-0552
Pitavastatin induces plaque stabilization in Watanabe heritable hyperlipidemic rabbits
H. Kobayashi 1 , H. Suzuki 1 , F. Sato 1 , Y. Yonemitsu 2 , Y. Nakashima 2 , K. Sueishi 2 . 1 Kowa Company, Ltd., Tokyo; 2 Kyushu University, Japan Objective: To investigate the effect of pitavastatin, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor with a strong cholesterollowering activity, on plaque stabilization in Watanabe heritable hyperlipidemic (WHHL) rabbits. Methods: Twenty-two male WHHL rabbits aged 3 months were divided into two groups, a control group and a pitavastatin group. Pitavastatin was administered to WHHL rabbits in drinking water (0.5mg equivalent/kg/day) for 16 weeks. The plaque stabilization was assessed by immunohistochemistry. Results: Pitavastatin significantly reduced the plasma total cholesterol (TC), very low density lipoprotein (VLDL)-C, intermediate density lipoprotein (IDL)-C and low density lipoprotein (LDL)-C (28.6, 60.0, 42.3 and 21.7%, respectively). In the aorta, pitavastatin reduced the surface lesion area (38.6%). In the histopathological study, pitavastatin decreased the percent area
XIIIth International Symposium on Atherosclerosis, September 28–October 2, 2003, Kyoto, Japan