Phosphatidylcholine (PC), the major source of dietary choline, has been demonstrated to improve t... more Phosphatidylcholine (PC), the major source of dietary choline, has been demonstrated to improve the capability of learning and memory in rodent and the amelioration of long-chain n-3 polyunsaturated fatty acids (PUFA) on anti-aging and anti-oxidation is widely known as well. In this study, three kinds of PC were chose to demonstrate the role of different fatty acids composition on glycerol backbone in improving the brain function of mice induced by scopolamine which was used to impair cholinergic system and cause oxidative stress. Male BALB/c mice were randomly divided into 5 groups: model (M) group, control (Con) group, egg yolk lecithin (EL) group, squid PC (SQ-PC) group and sea cucumber PC (SC-PC) group. The intraperitoneal injection of scopolamine hydrobromide (5 mg/kg) was carried out on the 8(th) of group feeding and sustained daily until the end of test. Morris water maze test was used to evaluate the improvement of cognitive decline and the activity of acetylcholinesterase (...
Dietary sterols are catabolized into various substances in the intestinal tract. Dietary 3-oxo de... more Dietary sterols are catabolized into various substances in the intestinal tract. Dietary 3-oxo derivatives of cholesterol and plant sterols (e.g., cholest-4-en-3-one and campest-5-en-3-one) have been shown to have anti-obesity effects. In this study, we tested whether feeding cholest-5-en-3-one (5-cholestenone), a cholesterol metabolite, to db/db mice protects them from obesity-associated metabolic disorders. In db/db mice, dietary 5-cholestenone significantly alleviated hepatomegaly and elevated serum triglyceride levels; however, the effect was not sufficient to improve hepatic steatosis and obesity. On the other hand, hyperglycemia and severe hyperinsulinemia in control db/db mice were markedly attenuated in 5-cholestenone-fed db/db mice. The production of inflammatory cytokines, such as monocyte chemoattractant protein-1, interleukin-6, and tumor necrosis factor-alpha (TNFα), was decreased, suggesting that the suppressive actions of 5-cholestenone were attributable to the allevi...
Conjugated fatty acid, the general term of positional and geometric isomers of polyunsaturated fa... more Conjugated fatty acid, the general term of positional and geometric isomers of polyunsaturated fatty acids with conjugated double bonds, has attracted considerable attention because of its potentially beneficial biological effects. In the present study, dietary effect of pomegranate seed oil rich in punicic acid (9cis, 11trans, 13cis-conjugated linolenic acid; 9c, 11t, 13c-CLNA) on lipid metabolism was investigated in obese, hyperlipidemic Otsuka Long-Evans Tokushima Fatty (OLETF) rats. After 2 weeks feeding period, OLETF rats revealed obesity and hyperlipidemia compared with their progenitor LETO rats. Feeding of the diet supplemented with 9% safflower oil and 1% pomegranate seed oil (9c, 11t, 13c-CLNA diet) did not affect abdominal white adipose tissue weights and serum lipid levels compared with the diet supplemented with 10% safflower oil (control diet) in OLETF rats. However, the accumulated hepatic triacylglycerol was markedly decreased by 9c, 11t, 13c-CLNA diet in OLETF rats....
The effects of the addition of a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibi... more The effects of the addition of a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, simvastatin, to the medium on sterol synthesis and phosphatidylcholine (PC) synthesis were studied in HepG2 cells. The cells were cultured with simvastatin at concentrations of 10(-7) and 10(-6) mol/L for 6 hours, and radioactive lipid precursors were added 1 hour before harvesting. Simvastatin inhibited cholesterol synthesis from [14C]acetate in a dose-dependent manner. It also decreased the incorporation of [14C]choline into PC by 30%; this decrease was accompanied by a decrease in phosphocholine cytidylyltransferase activity in cell homogenates. Simvastatin had no significant effects on the incorporation of [3H]glycerol into phospholipids. These data indicate that simvastatin has two different functions: inhibition of HMG-CoA reductase and depression of de novo synthesis of PC via the cytidine diphosphate-choline pathway, which, in turn, may result in a decrease in plasma lipid l...
Background Lipodystrophies are rare acquired and genetic disorders characterized by the complete ... more Background Lipodystrophies are rare acquired and genetic disorders characterized by the complete or partial absence of body fat with a line of metabolic disorders. Previous studies demonstrated that dietary conjugated linoleic acid (CLA) induces hepatic steatosis and hyperinsulinemia through the drastic reduction of adipocytokine levels due to a paucity of adipose tissue in mice and the pathogenesis of these metabolic abnormalities in CLA-fed mice is similar to that in human lipodystrophy. The present study explores the effect of leptin infusion on the pathogenesis of diet-induced lipodystrophy in mice. C57BL/6N mice were assigned to three groups: (1) mice were fed a semisynthetic diet supplemented with 6% corn oil and infused PBS intraperitoneally (normal group), (2) mice were fed a semisynthetic diet supplemented with 4% corn oil plus 2% CLA and infused PBS intraperitoneally (lipodystrophy-control group), and (3) mice were fed a semisynthetic diet supplemented with 4% corn oil plu...
Lipoprotein(a) [Lp(a)], a lipoprotein that structurally resembles low-density lipoprotein (LDL), ... more Lipoprotein(a) [Lp(a)], a lipoprotein that structurally resembles low-density lipoprotein (LDL), contains apolipoprotein(a) [apo(a)] and apolipoprotein B-100 (apo B). There exists a close inverse correlation between serum concentrations of LDL or apo B and concentrations of thyroid hormone in patients with thyroid disease, probably due to a change in LDL receptor activity. To clarify the relations between thyroid hormone and Lp(a), we measured serum Lp(a) levels in 13 hyperthyroid subjects before treatment (stage H), during the euthyroid stage induced immediately before performing a subtotal thyroidectomy (stage E), and during the hypothyroid stage observed transiently after the operation (stage L). The mean serum concentration of Lp(a) increased significantly (P = .01) from 9.4 mg/dL in stage H to 26.8 in stage L through the level of 15.5 mg/dL in stage E. There was no significant difference between the mean serum concentration of Lp(a) in these patients in stage E and healthy controls (14.2 mg/dL). There was a low but statistically significant negative correlation between the Lp(a) level and the serum free thyroxine (fT4) concentration (r = .31, P < .05). The results suggest that thyroid hormone is a potent modulator of Lp(a) metabolism.
Phosphatidylcholine (PC), the major source of dietary choline, has been demonstrated to improve t... more Phosphatidylcholine (PC), the major source of dietary choline, has been demonstrated to improve the capability of learning and memory in rodent and the amelioration of long-chain n-3 polyunsaturated fatty acids (PUFA) on anti-aging and anti-oxidation is widely known as well. In this study, three kinds of PC were chose to demonstrate the role of different fatty acids composition on glycerol backbone in improving the brain function of mice induced by scopolamine which was used to impair cholinergic system and cause oxidative stress. Male BALB/c mice were randomly divided into 5 groups: model (M) group, control (Con) group, egg yolk lecithin (EL) group, squid PC (SQ-PC) group and sea cucumber PC (SC-PC) group. The intraperitoneal injection of scopolamine hydrobromide (5 mg/kg) was carried out on the 8(th) of group feeding and sustained daily until the end of test. Morris water maze test was used to evaluate the improvement of cognitive decline and the activity of acetylcholinesterase (...
Dietary sterols are catabolized into various substances in the intestinal tract. Dietary 3-oxo de... more Dietary sterols are catabolized into various substances in the intestinal tract. Dietary 3-oxo derivatives of cholesterol and plant sterols (e.g., cholest-4-en-3-one and campest-5-en-3-one) have been shown to have anti-obesity effects. In this study, we tested whether feeding cholest-5-en-3-one (5-cholestenone), a cholesterol metabolite, to db/db mice protects them from obesity-associated metabolic disorders. In db/db mice, dietary 5-cholestenone significantly alleviated hepatomegaly and elevated serum triglyceride levels; however, the effect was not sufficient to improve hepatic steatosis and obesity. On the other hand, hyperglycemia and severe hyperinsulinemia in control db/db mice were markedly attenuated in 5-cholestenone-fed db/db mice. The production of inflammatory cytokines, such as monocyte chemoattractant protein-1, interleukin-6, and tumor necrosis factor-alpha (TNFα), was decreased, suggesting that the suppressive actions of 5-cholestenone were attributable to the allevi...
Conjugated fatty acid, the general term of positional and geometric isomers of polyunsaturated fa... more Conjugated fatty acid, the general term of positional and geometric isomers of polyunsaturated fatty acids with conjugated double bonds, has attracted considerable attention because of its potentially beneficial biological effects. In the present study, dietary effect of pomegranate seed oil rich in punicic acid (9cis, 11trans, 13cis-conjugated linolenic acid; 9c, 11t, 13c-CLNA) on lipid metabolism was investigated in obese, hyperlipidemic Otsuka Long-Evans Tokushima Fatty (OLETF) rats. After 2 weeks feeding period, OLETF rats revealed obesity and hyperlipidemia compared with their progenitor LETO rats. Feeding of the diet supplemented with 9% safflower oil and 1% pomegranate seed oil (9c, 11t, 13c-CLNA diet) did not affect abdominal white adipose tissue weights and serum lipid levels compared with the diet supplemented with 10% safflower oil (control diet) in OLETF rats. However, the accumulated hepatic triacylglycerol was markedly decreased by 9c, 11t, 13c-CLNA diet in OLETF rats....
The effects of the addition of a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibi... more The effects of the addition of a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, simvastatin, to the medium on sterol synthesis and phosphatidylcholine (PC) synthesis were studied in HepG2 cells. The cells were cultured with simvastatin at concentrations of 10(-7) and 10(-6) mol/L for 6 hours, and radioactive lipid precursors were added 1 hour before harvesting. Simvastatin inhibited cholesterol synthesis from [14C]acetate in a dose-dependent manner. It also decreased the incorporation of [14C]choline into PC by 30%; this decrease was accompanied by a decrease in phosphocholine cytidylyltransferase activity in cell homogenates. Simvastatin had no significant effects on the incorporation of [3H]glycerol into phospholipids. These data indicate that simvastatin has two different functions: inhibition of HMG-CoA reductase and depression of de novo synthesis of PC via the cytidine diphosphate-choline pathway, which, in turn, may result in a decrease in plasma lipid l...
Background Lipodystrophies are rare acquired and genetic disorders characterized by the complete ... more Background Lipodystrophies are rare acquired and genetic disorders characterized by the complete or partial absence of body fat with a line of metabolic disorders. Previous studies demonstrated that dietary conjugated linoleic acid (CLA) induces hepatic steatosis and hyperinsulinemia through the drastic reduction of adipocytokine levels due to a paucity of adipose tissue in mice and the pathogenesis of these metabolic abnormalities in CLA-fed mice is similar to that in human lipodystrophy. The present study explores the effect of leptin infusion on the pathogenesis of diet-induced lipodystrophy in mice. C57BL/6N mice were assigned to three groups: (1) mice were fed a semisynthetic diet supplemented with 6% corn oil and infused PBS intraperitoneally (normal group), (2) mice were fed a semisynthetic diet supplemented with 4% corn oil plus 2% CLA and infused PBS intraperitoneally (lipodystrophy-control group), and (3) mice were fed a semisynthetic diet supplemented with 4% corn oil plu...
Lipoprotein(a) [Lp(a)], a lipoprotein that structurally resembles low-density lipoprotein (LDL), ... more Lipoprotein(a) [Lp(a)], a lipoprotein that structurally resembles low-density lipoprotein (LDL), contains apolipoprotein(a) [apo(a)] and apolipoprotein B-100 (apo B). There exists a close inverse correlation between serum concentrations of LDL or apo B and concentrations of thyroid hormone in patients with thyroid disease, probably due to a change in LDL receptor activity. To clarify the relations between thyroid hormone and Lp(a), we measured serum Lp(a) levels in 13 hyperthyroid subjects before treatment (stage H), during the euthyroid stage induced immediately before performing a subtotal thyroidectomy (stage E), and during the hypothyroid stage observed transiently after the operation (stage L). The mean serum concentration of Lp(a) increased significantly (P = .01) from 9.4 mg/dL in stage H to 26.8 in stage L through the level of 15.5 mg/dL in stage E. There was no significant difference between the mean serum concentration of Lp(a) in these patients in stage E and healthy controls (14.2 mg/dL). There was a low but statistically significant negative correlation between the Lp(a) level and the serum free thyroxine (fT4) concentration (r = .31, P < .05). The results suggest that thyroid hormone is a potent modulator of Lp(a) metabolism.
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