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1.
Int J Clin Pract ; 68(9): 1065-73, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24898471

RESUMO

AIMS: To assess fesoterodine 8 mg efficacy over time and vs. placebo in subjects with overactive bladder (OAB) who responded suboptimally to tolterodine extended release (ER) 4 mg. METHODS: In a 12-week, double-blind trial, subjects with self-reported OAB symptoms for ≥ 6 months, mean of ≥ 8 micturitions and ≥ 2 to < 15 urgency urinary incontinence (UUI) episodes/24 h, and suboptimal response to tolterodine ER 4 mg (defined as ≤ 50% reduction in UUI episodes during 2-week run-in) were randomised to fesoterodine (4 mg for 1 week, 8 mg for 11 weeks) or placebo once daily. Change from baseline to week 12 in UUI episodes (primary end-point) was analysed in step-wise fashion: first, baseline vs. week 12 for fesoterodine; if significant, then change from baseline to week 12 for fesoterodine vs. placebo. RESULTS: By week 12, subjects receiving fesoterodine 8 mg had significantly greater improvement from baseline vs. placebo in UUI episodes, urgency episodes and scores on the Patient Perception of Bladder Control, Urgency Perception Scale and OAB Questionnaire Symptom Bother and Health-Related Quality of Life scales and domains (all p < 0.05). 50% and 70% UUI responder rates were also significantly higher with fesoterodine 8 mg vs. placebo at week 12 (p < 0.05). Dry mouth (placebo, 4%, 12/301; fesoterodine, 16.6%, 51/308) and constipation (placebo, 1.3%, 4/301; fesoterodine, 3.9%, 12/308) were the most frequent adverse events. CONCLUSIONS: Subjects who responded suboptimally to tolterodine ER 4 mg showed significant improvements in UUI and other OAB symptoms and patient-reported outcomes, with good tolerability, during treatment with fesoterodine 8 mg vs. placebo.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Antagonistas Muscarínicos/efeitos adversos , Tartarato de Tolterodina/uso terapêutico , Resultado do Tratamento , Bexiga Urinária Hiperativa/tratamento farmacológico , Adulto , Idoso , Compostos Benzidrílicos/administração & dosagem , Compostos Benzidrílicos/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antagonistas Muscarínicos/administração & dosagem , Antagonistas Muscarínicos/uso terapêutico , Qualidade de Vida , Inquéritos e Questionários , Tartarato de Tolterodina/administração & dosagem
2.
Biochim Biophys Acta ; 1390(3): 237-44, 1998 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-9487145

RESUMO

To examine how variable sitostanol (SI) levels in phytosterol-supplemented diets influence plasma and hepatic lipid concentrations, fifty hamsters were divided into five groups and fed semipurified diets containing 0.25% (w/w) cholesterol for 45 days ad libitum. Four groups were fed this diet with 1% (w/w) phytosterol mixtures which contained 0.01% (w/w) SI derived from soybean, 0.2% (w/w) SI derived from tall oil, 0.2% (w/w) synthetic SI mixture (SIM) and 1% (w/w) pure SI, respectively. A control group did not receive phytosterols. Dietary SI supplementation at 1% (w/w) decreased total and non-apolipoprotein-A cholesterol levels in plasma by 34% (P=0.001) and 55% (P=0.04), respectively, whereas mean plasma total cholesterol level in the 0.2% (w/w) SI group was 23% (P=0.001) lower than that of the control group. Conversely, plasma lipid profile in hamsters fed 1 or 0.2% (w/w) SI did not differ from the 0.01% (w/w) SI group. Liver weights were 15 and 20% (P=0.012) higher in the control group compared with those fed 0.01% and 1% (w/w) SI, respectively, while the hepatic cholesterol content in the control group was greater (P<0.0001) than that of all other groups. Plasma campesterol levels were higher (P=0.04) in the 0.01% and 0.2% (w/w) SI fed groups than in the control, 0.2% (w/w) SIM and 1% (w/w) SI groups. Hepatic sitosterol content was elevated (P=0.002) in the SIM fed group compared to other groups. We conclude that dietary SI effect is proportional to its concentration in phytosterol mixtures and in the diet. Dietary SI lowered plasma cholesterol levels at concentrations higher than 0.2% (w/w) in hamsters. (c) 1998 Elsevier Science B.V.


Assuntos
Anticolesterolemiantes/farmacologia , Lipídeos/sangue , Fitosteróis/metabolismo , Óleos de Plantas , Sitosteroides/farmacologia , Animais , Anticolesterolemiantes/administração & dosagem , Peso Corporal , Colesterol/análogos & derivados , Colesterol/metabolismo , HDL-Colesterol/sangue , Cricetinae , Dieta , Ingestão de Alimentos , Fígado/metabolismo , Tamanho do Órgão , Fitosteróis/administração & dosagem , Sitosteroides/administração & dosagem
3.
Am J Clin Nutr ; 69(6): 1144-50, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10357732

RESUMO

BACKGROUND: Dietary plant sterols (phytosterols) have been shown to lower plasma lipid concentrations in animals and humans. However, the effect of phytosterol intake from tall oil on cholesterol and phytosterol metabolism has not been assessed in subjects fed precisely controlled diets. OBJECTIVE: Our objective was to examine the effects of sitostanol-containing phytosterols on plasma lipid and phytosterol concentrations and de novo cholesterol synthesis rate in the context of a controlled diet. DESIGN: Thirty-two hypercholesterolemic men were fed either a diet of prepared foods alone or a diet containing 1.7 g phytosterols/d for 30 d in a parallel study design. RESULTS: No overall effects of diet on total cholesterol concentrations were observed, although concentrations were lower with the phytosterol-enriched than with the control diet on day 30 (P < 0.05). LDL-cholesterol concentrations on day 30 had decreased by 8.9% (P < 0.01) and 24.4% (P < 0.001) with the control and phytosterol-enriched diets, respectively. HDL-cholesterol and triacylglycerol concentrations did not change significantly. Moreover, changes in circulating campesterol and beta-sitosterol concentrations were not significantly different between phytosterol-fed and control subjects. In addition, there were no significant differences in fractional (0.091 +/- 0.028 and 0.091 +/- 0.026 pool/d, respectively) or absolute (0.61 +/- 0.24 and 0.65 +/- 0.23 g/d, respectively) synthesis rates of cholesterol observed between control and phytosterol-fed subjects. CONCLUSION: Addition of blended phytosterols to a prudent North American diet improved plasma LDL-cholesterol concentrations by mechanisms that did not result in significant changes in endogenous cholesterol synthesis in hypercholesterolemic men.


Assuntos
Anticolesterolemiantes/administração & dosagem , HDL-Colesterol/sangue , Hiperlipidemias/tratamento farmacológico , Fitosteróis/administração & dosagem , Sitosteroides/administração & dosagem , Adulto , Anticolesterolemiantes/uso terapêutico , Colesterol/análogos & derivados , Colesterol/sangue , HDL-Colesterol/biossíntese , LDL-Colesterol/sangue , Cromatografia Gasosa , Humanos , Hiperlipidemias/dietoterapia , Masculino , Pessoa de Meia-Idade , Fitosteróis/sangue , Fitosteróis/uso terapêutico , Sitosteroides/uso terapêutico , Triglicerídeos/sangue
4.
Atherosclerosis ; 143(2): 341-51, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10217363

RESUMO

The aim of this study was to examine the efficacy of variable dietary sitostanol (SI) concentrations on cholesterol absorption, synthesis and excretion rates in two animal models. Hamsters and rabbits were fed semi-purified diets supplemented with cholesterol and 1% (w/w) phytosterols containing either 0.007, 0.17, 0.8 or 1% (w/w) SI. The control (0% (w/w) SI) groups consumed the same diets but no phytosterols were added. The dual-isotope plasma ratio of [13C]- and [18O]cholesterol and deuterium incorporation methods were applied to measure simultaneously cholesterol absorption and fractional synthesis, respectively. Plasma total cholesterol levels were lower in rabbits and hamsters fed 0.8 and 1% (w/w) SI, respectively, as compared to their controls. Percent cholesterol absorption was lower (P = 0.03) in hamsters fed 1% (w/w) SI (42.5 +/- 13.3%) than control (65.1 +/- 13.4%). Moreover, cholesterol excretion in the feces was 77 and 57% higher (P = 0.017) in the 1% (w/w) SI- relative to control- and 0.17% (w/w) SI-fed groups, respectively. In rabbits, cholesterol excretion was 64% higher (P = 0.018) in 0.8% (w/w) SI- compared with control-fed groups. Fractional synthesis rate was higher (P = 0.033) in hamsters fed 1% (w/w) SI (0.116 +/- 0.054 pool day(-1)) as compared to control (0.053 +/- 0.034 pool day(-1)). However, cholesterol synthesis rates did not vary among groups fed variable concentrations of SI. In rabbits, percent cholesterol absorption and its fractional synthesis rate varied but did not reach significance. Fractional synthesis rate in hamsters was correlated (r = -0.32, P = 0.03) with percent cholesterol absorption. In conclusion, dietary SI exhibited a dose-dependent action in inhibiting cholesterol absorption while increasing cholesterol excretion and upregulating cholesterogenesis in hamsters resulting in lower circulating lipid levels.


Assuntos
Anticolesterolemiantes/farmacologia , Colesterol na Dieta/farmacocinética , Colesterol/metabolismo , Sitosteroides/farmacologia , Análise de Variância , Animais , Colesterol na Dieta/administração & dosagem , Cricetinae , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fezes/química , Lipídeos/sangue , Masculino , Fitosteróis/sangue , Coelhos , Valores de Referência , Especificidade da Espécie
5.
Atherosclerosis ; 138(1): 101-10, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9678775

RESUMO

The effects of graded amounts of dietary sitostanol (0.01, 0.2 and 0.8% (w/w)) were examined on plasma lipid-profile, coronary artery plaque development and lecithin:cholesterol acyl transferase activity in male New Zealand White rabbits given semi-purified diets for 10 weeks. All diets provided < 10% energy in the form of fat and contained 0.5% (w/w) cholesterol (C). Rabbits fed the semi-purified diet with 0.8% (w/w) (0.64 g/day) sitostanol had lower plasma total cholesterol (TC) (p = 0.006) (15.2 +/- 4.80 mmol/l) and very low-density lipoprotein-cholesterol (VLDL-C) (p = 0.007) (6.31 +/- 3.11 mmol/l) levels compared to the atherogenic control group (n = 6) (29.6 +/- 5.52 and 17.16 +/- 7.43 mmol/l, respectively). Dietary sitostanol at 0.8% (w/w) depressed plaque accretion in coronary arteries (p = 0.0014) and ascending aorta (p = 0.0004) compared with the atherogenic control, 0.01 and 0.2% (w/w) sitostanol-fed groups. No differences (p = 0.24) in the activity of lecithin:cholesterol acyl transferase (LCAT) were observed across groups, although plasma cholesterol fractional esterification rate was higher (p = 0.004) in the 0.8% (w/w) sitostanol fed animals compared with the atherogenic control. Significant negative correlations were demonstrated between sitostanol intake and plasma TC, LDL-C and VLDL-C levels. Hepatic campesterol levels were correlated (r = 0.3, p = 0.03) with plasma but not hepatic TC concentrations. These results demonstrate that dietary sitostanol at a concentration of 0.8% (w/w) or 0.64 g/day lowered plasma cholesterol levels and depressed atherosclerosis development in rabbits, but did not alter LCAT activity.


Assuntos
Anticolesterolemiantes/administração & dosagem , Arteriosclerose/patologia , Vasos Coronários/patologia , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Sitosteroides/administração & dosagem , Animais , Anticolesterolemiantes/farmacologia , Arteriosclerose/metabolismo , Colesterol/sangue , Colesterol/metabolismo , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/enzimologia , Dieta , Esterificação , Masculino , Fitosteróis/farmacologia , Coelhos , Sitosteroides/farmacologia
6.
Nutr Rev ; 56(8): 245-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9735678

RESUMO

A recent study in The Netherlands compared the effects of margarine enriched with different vegetable oil sterols with margarine containing sitostanol-ester on plasma total, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol concentrations. Margarine with sterolesters from soybean oil (mainly esters from sitosterol, campesterol, and stigmasterol) was as effective as a margarine with sitostanol-ester in lowering blood total and LDL cholesterol levels without affecting HDL cholesterol levels.


Assuntos
HDL-Colesterol/efeitos dos fármacos , LDL-Colesterol/efeitos dos fármacos , Óleos de Plantas/farmacologia , Esteróis/farmacologia , Adulto , Idoso , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Método Duplo-Cego , Feminino , Humanos , Hidrogenação , Masculino , Margarina , Pessoa de Meia-Idade , Óleos de Plantas/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Esteróis/administração & dosagem
7.
Metabolism ; 48(1): 68-73, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9920147

RESUMO

To investigate the potential effects of high-dose 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor on plasma phytosterol, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG), hypercholesterolemic subjects received 40 or 80 mg/d simvastatin in a 24-week prospective clinical trial. Plasma lipid levels were analyzed enzymatically, and plasma phytosterol concentrations were determined using gas-liquid chromatography. The change in the plasma phytosterol-campesterol level was used as an indicator of cholesterol absorption in humans. Simvastatin treatment reduced plasma campesterol (-24%, P = .017) but did not affect circulating stigmasterol and sitosterol levels. A dose of 80 mg/d simvastatin produced a larger decrease (P = .050) in plasma campesterol (0.1680 mmol/L) than 40 mg/d (0.0237 mmol/L) versus baseline. There was a positive correlation between plasma campesterol and TC both before (r = .54, P = .027) and after (r = .63, P = .009) treatment. Plasma TC and TG levels did not differ between groups receiving 40 or 80 mg/d simvastatin. Simvastatin treatment reduced circulating TC, LDL-C, and TG by 40%, 50%, and 33% (P<.007), respectively. There was no significant effect of simvastatin on plasma HDL-C, but the HDL-C/LDL-C ratio increased 1.3-fold (P<.0001). In conclusion, this HMG-CoA reductase inhibitor reduces the plasma campesterol level, a marker of cholesterol absorption, which may contribute to the mechanism by which simvastatin decreases circulating cholesterol levels.


Assuntos
Colesterol/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipercolesterolemia/metabolismo , Absorção Intestinal , Fitosteróis/metabolismo , Sinvastatina/farmacologia , Adulto , Idoso , Feminino , Humanos , Hipercolesterolemia/tratamento farmacológico , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade
8.
Prostaglandins Leukot Essent Fatty Acids ; 55(5): 293-302, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8981625

RESUMO

The objective of the present study was to examine the effect of modifying the fatty acid composition of membranes on cell growth and phosphoinositide specific phospholipase C (PLC) activity in HT-29 colon cancer cells. Cells were seeded at a density of 12 x 10(3) cells/cm2 and supplemented with 30 microM of either 18:0, 18:2 (n6) or 18:3 (n3) complexed to bovine serum albumin (BSA) in DMEM medium. Cell growth was followed for 12 days. The 18:0 supplemented cells (control) reached maximum growth at day nine which was greater than either 18:2 (n6) or 18:3 (n3) supplemented cells. There was no difference between the latter two groups in their growth. To investigate the fatty acid incorporation of the supplemented fatty acid and how they may influence composition in the cell membrane, we examined the fatty acid composition of each phospholipid (PL) species. Both phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were significantly influenced by the type of fatty acid supplemented. Supplementation with 18:0 resulted in HT-29 cell membranes having more monounsaturated fatty acids than the cells grown in the other fatty acids. Polyunsaturated fatty acid (PUFA) supplementation (both 18:2 and 18:3) resulted in the enrichment of PUFA in the PL fractions. Cells supplemented with 18:3 (n3) had the highest unsaturation index in membrane PE as compared to the other phospholipid species. PLC activity of the membranes was measured using PIP2 as a substrate in the presence of 15 micrograms alamethicin and 42 microM free calcium. The contribution of G protein to the activity of the enzyme was assessed using GTP gamma(S). PLC activity of HT-29 cells was 16% higher in the presence of GTP gamma(S) response. GTP gamma(S)-activated PLC activity of 18:3 (n3) supplemented cells was 81% of those supplemented with either 18:0 or 18:2 (n6) cells. It is concluded that the decrease in cell proliferation with supplementation with 18:3 (n3) may be mediated through its inhibitory effect on PLC, which provides the second messengers for protein kinase C (PKC) activation. PLC may be influenced by an increased unsaturation index of the PE fraction of the HT-29 tumor cell membranes.


Assuntos
Neoplasias do Colo/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Lipídeos de Membrana/química , Fosfolipídeos/metabolismo , Fosfolipases Tipo C/metabolismo , Alameticina/farmacologia , Cálcio/metabolismo , Carbacol/farmacologia , Divisão Celular , Neoplasias do Colo/patologia , Ácido Desoxicólico/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Guanosina Difosfato/farmacologia , Guanosina Trifosfato/farmacologia , Humanos , Lipídeos de Membrana/metabolismo , Fosfatidilcolinas/análise , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/análise , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/metabolismo , Fosfatidilinositóis/análise , Fosfatidilinositóis/química , Fosfatidilinositóis/metabolismo , Fosfatidilserinas/análise , Fosfatidilserinas/química , Fosfatidilserinas/metabolismo , Fosfolipídeos/análise , Fosfolipídeos/química , Esfingomielinas/análise , Esfingomielinas/química , Esfingomielinas/metabolismo , Células Tumorais Cultivadas , Fosfolipases Tipo C/análise , Fosfolipases Tipo C/efeitos dos fármacos
9.
Eur J Clin Nutr ; 58(12): 1612-20, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15199384

RESUMO

OBJECTIVE: To study the compliance and changes in plasma lipids, plant sterols, fat-soluble vitamins and carotenoids in children and parents with familial hypercholesterolemia (FH) consuming a plant sterol ester-enriched (PSE) spread. DESIGN: A 26-week open-label follow-up of children who had previously been studied in a controlled cross-over design. The parents were also included in the open-label arm of the study. SETTING: Outpatient clinic for treatment of hyperlipidemia. SUBJECTS: A total of 37 children (7-13 y) and 20 parents (32-51 y) diagnosed with 'definite' or 'possible' heterozygous FH. In all, 19 of the parents, but no children, used statins. All were patients at the Lipid Clinic, National Hospital in Oslo. INTERVENTIONS: Subjects were recommended to eat 20 g/day of PSE spread as part of their lipid-lowering diet. RESULTS: The mean intake of PSE spread was 13.7 and 16.5 g/days in the children and parents, respectively, corresponding to 1.2 and 1.5 g of plant sterols. Plasma total cholesterol decreased by 9.1% in both children (P<0.001) and parents (P=0.002). The corresponding decreases in LDL cholesterol were 11.4% (P<0.001) and 11.0% (P=0.012). Increases in serum lathosterol, campesterol and sitosterol, adjusted for total cholesterol, were observed in the children (31, 96, 48%, respectively, P<0.001) at the end of the controlled cross-over period. In the parents, serum campesterol and sitosterol, adjusted for total cholesterol, increased by 92 and 39%, respectively (P< 0.001). Lipid-adjusted serum alpha- and beta-carotene decreased by 17.4% (P=0.008) and 10.9% (P=0.018), respectively, in the children at the end of the controlled PSE period, but increased again during the follow-up. In the parents, serum alpha- and beta-carotene concentrations were unchanged, while serum lutein and lycopene decreased by 7.3% (P=0.037) and 14.6% (P=0.044), respectively. CONCLUSIONS: Sustained efficacy of cholesterol reduction and long-term compliance of PSE intake were demonstrated in this study.


Assuntos
Carotenoides/sangue , Colesterol/análogos & derivados , Colesterol/sangue , Hiperlipoproteinemia Tipo II/dietoterapia , Lipídeos/sangue , Margarina , Fitosteróis/administração & dosagem , Adolescente , Adulto , Criança , Estudos Cross-Over , Feminino , Humanos , Hiperlipoproteinemia Tipo II/sangue , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Sitosteroides , Resultado do Tratamento
10.
Eur J Clin Nutr ; 57(5): 681-92, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12771969

RESUMO

OBJECTIVE: To evaluate both efficacy and safety in humans of long-term consumption of spreads containing plant sterol esters. DESIGN: Randomized double-blind placebo-controlled parallel trial. SUBJECTS: : Hundred and eighty-five healthy volunteers (35-64 y). INTERVENTION: Volunteers daily consumed 20 g spread enriched with 1.6 g plant sterols as fatty acid esters or a control spread for 1 y. They continued their habitual diet and lifestyle. Outcome measures included efficacy markers such as total and LDL-cholesterol, a large range of safety parameters, and reporting of adverse events. RESULTS: Consumption of the plant sterol ester-enriched spread consistently lowered total and LDL cholesterol during the 1 y period on average by 4 and 6%, respectively (0.01 < P < 0.05). Plant sterols intake did on average not result in a lower carotenoid concentration (when expressed per LDL-cholesterol) after 52 weeks (P>0.05). However, carotenoid concentrations changed over time. Plant sterols intake reduced lipid adjusted alpha- and beta-carotene-concentrations by only 15-25% after 1 y, relative to control. Lipid-adjusted fat-soluble vitamin concentrations remained unchanged. Plant sterol concentrations in serum were increased from 2.76 to 5.31 ( micro mol/mmol total cholesterol) for campesterol (P<0.0001) and from 1.86 to 2.47 ( micro mol/mmol total cholesterol) for beta-sitosterol (P<0.0001). The increase in total plant sterol concentration in red blood cells (5.29-9.62 micro g/g) did not affect red blood cell deformability. Hormone levels in males (free and total testosterone) and females (luteinizing hormone, follicle stimulating hormone, beta-estradiol and progesterone) as well as all clinical chemical and hematological parameters measured were unaffected. Adverse events reported were not different between subjects consuming control spread and subjects consuming plant sterol esters-enriched spread. CONCLUSION: Consumption of a plant sterol esters-enriched spread is an effective way to consistently lower blood cholesterol concentrations and is safe to use over a long period of time.


Assuntos
Colesterol/análogos & derivados , Dieta , Ésteres/administração & dosagem , Fitosteróis/administração & dosagem , Adulto , Carotenoides/sangue , Colesterol/sangue , LDL-Colesterol/sangue , Gorduras na Dieta/administração & dosagem , Método Duplo-Cego , Ésteres/efeitos adversos , Feminino , Humanos , Masculino , Margarina , Pessoa de Meia-Idade , Fitosteróis/efeitos adversos , Placebos , Sitosteroides/sangue , beta Caroteno/sangue
11.
Can J Physiol Pharmacol ; 76(7-8): 780-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10030459

RESUMO

To examine the effect of gender on the mechanisms of action of phytosterols extracted from tall oil (TO) and soybean (SB) on cholesterol and phytosterol metabolism, male and female hamsters were fed cholesterol-enriched diets containing 0.5 or 1% (w/w) TO or SB phytosterols for 90 days. Plasma lipoprotein cholesterol profile and tissue phytosterol and cholesterol biosynthesis levels were determined. Mean plasma total-cholesterol level in females fed 1% (w/w) SB was reduced (p<0.05) by 44%, while in males it was lowered (p<0.05) by 25% compared with their respective controls. Moreover, mean plasma total-cholesterol level was reduced (p<0.05) in male hamsters by -31% and female hamsters by -32% when fed 1% (w/w) TO. Cholesterol biosynthesis was higher (p<0.05) by twofold in groups fed TO at 0.5 and 1% (w/w) concentrations, compared with SB. Hamsters fed TO at 0.5 and 1% (w/w) levels also had higher (p<0.05) hepatic and enterocytic campesterol contents than SB-fed animals. These findings demonstrate gender differences in cholesterol metabolism in TO- and SB-fed hamsters. The results suggest that TO, conversely to SB phytosterol, is a more effective cholesterol-lowering agent in male, but not as much in female, hamsters, over a feeding period of 90 days.


Assuntos
Anticolesterolemiantes/farmacologia , Colesterol/biossíntese , Glycine max/química , Fitosteróis/farmacologia , Óleos de Plantas/química , Animais , Anticolesterolemiantes/análise , Peso Corporal/efeitos dos fármacos , Colesterol/análogos & derivados , Cricetinae , Dieta , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Mucosa Intestinal/metabolismo , Intestinos/química , Intestinos/citologia , Lipídeos/sangue , Fígado/química , Fígado/citologia , Fígado/metabolismo , Masculino , Mesocricetus , Fitosteróis/análise , Fatores Sexuais , Sitosteroides/análise
12.
Can J Physiol Pharmacol ; 75(3): 217-27, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9164705

RESUMO

Phytosterols (plant sterols), abundant in fat-soluble fractions of plants, are consumed at levels of 200-400 mg/day in Western diets. Chemically resembling cholesterol, phytosterols inhibit the absorption of cholesterol. Phytosterol consumption in human subjects under a wide range of study conditions has been shown to reduce plasma total and low density lipoprotein (LDL) cholesterol levels; however, the response varies widely. Greater cholesterol-lowering efficacy occurs with consumption of the saturated phytosterol sitostanol versus sitosterol or campesterol. Most studies report no effect of phytosterol administration in high density lipoprotein (HDL) cholesterol or triglyceride levels, although certain evidence exists for an HDL cholesterol raising effect of sitostanol. Phytosterol absorption is limited, although serum phytosterol levels have proven to be important indicators of both cholesterol absorption and synthesis. Serum phytosterols correlate with HDL cholesterol level. In addition, higher phytosterol/cholesterol ratios appear in HDL versus LDL particles, suggesting the existence of an intrinsic phytosterol action, in addition to the extrinsic effect on cholesterol absorption. In conclusion, addition to diet of the phytosterol sitostanol represents an effective means of improving circulating lipid profiles to reduce risk of coronary heart disease.


Assuntos
Anticolesterolemiantes/administração & dosagem , Colesterol/sangue , Dieta , Fitosteróis/administração & dosagem , Anticolesterolemiantes/efeitos adversos , Anticolesterolemiantes/metabolismo , Colesterol/administração & dosagem , Colesterol/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Humanos , Fitosteróis/efeitos adversos , Fitosteróis/metabolismo
13.
J Surg Res ; 92(2): 201-5, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10896822

RESUMO

BACKGROUND: Diets rich in omega-3 fatty acids have been shown to decrease both the initiation and promotion of colon carcinogenesis although their effect on hepatic metastasis formation is less well understood. Since adhesion of human colorectal carcinoma (HCRC) cells to hepatic endothelial cells is an important step in the metastatic cascade, the effect of membrane omega-3 fatty acid alterations on endothelial cell adhesion was studied. MATERIALS AND METHODS: CX-1 cells, a moderately differentiated HCRC cell line known to produce hepatic metastases in an athymic mouse intrasplenic injection model, were used. Cells were grown in omega-3 fatty acid-enriched medium and membrane-free fatty acid modifications confirmed with gas chromatography. Both human umbilical vein and hepatic sinusoidal endothelial cells were used in the binding assays. Adhesion assays were performed in a standard fashion using (51)Cr-labeled cells to tumor necrosis factor (TNF)-stimulated endothelial cell monolayers. Immunohistochemical analysis was performed for sialyl-Lewis(x), the receptor involved in endothelial adhesion on the surface of control and fatty acid-modified cells. RESULTS: Gas chromatographic analysis confirmed membrane fatty acid modification of CX-1 cells by growth in docosahexanoic acid (omega-3) (4.761 nmol/10(6) cells vs 0.057 nmol/10(6) cells for controls). Binding of CX-1 to both human umbilical vein and hepatic sinusoidal endothelial cells decreased from 38.4 +/- 0.44 to 11.58 +/- 0.87% (P < 0.01). Immunocytochemical analysis showed a decrease in sialyl-Lewis(x) expression with omega-3 treatment. CONCLUSIONS: These data indicate that omega-3 fatty acids may also be protective against the formation of hepatic metastases. The mechanism for this may be decreased endothelial cell adhesion which in turn may be due to decreased expression of the endothelial receptor sialyl-Lewis(x).


Assuntos
Adesão Celular/efeitos dos fármacos , Neoplasias Colorretais/fisiopatologia , Endotélio Vascular/fisiologia , Ácidos Graxos Ômega-3/farmacologia , Animais , Adesão Celular/fisiologia , Cromatografia Gasosa , Neoplasias Colorretais/patologia , Ácidos Docosa-Hexaenoicos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Oligossacarídeos/análise , Antígeno Sialil Lewis X , Células Tumorais Cultivadas , Veias Umbilicais
14.
J Lipid Res ; 41(5): 697-705, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10787430

RESUMO

It has been suggested that phytosterol and phytostanol esters possess similar cholesterol-lowering properties, however, whether mechanisms responsible are identical has not been addressed. To address this question, cholesterol plasma levels, absorption, biosynthesis, and turnover were measured in 15 hypercholesterolemic subjects consuming prepared diets each over 21 d using a cross-over design. Diets contained either i) margarine (M), ii) margarine with phytosterol esters (MSE) (1.84 g/d), or iii) margarine with phytostanol esters (MSA) (1.84 g/d). Cholesterol absorption was measured using the ratio of [(13)C]cholesterol(oral):D(7)-cholesterol(IV); biosynthesis using D incorporation from D(2)O and turnover by D(7)-cholesterol(IV) decay rates. Plasma total cholesterol level at d 21/22 was lower (P < 0. 05) for MSE (13.4%) but not MSA (10.2%) versus M (6.0%) diets. Plasma low density lipoprotein-cholesterol (LDL-C) mean reductions at d 21/22 were larger (P < 0.05) for MSE (12.9%) and MSA (7.9%) compared with M (3.9%). Plasma TG and high density lipoprotein-cholesterol (HDL-C) levels did not differ across diets. Cholesterol absorption was reduced (P < 0.05) 36.2 and 25.9% at d 21 for MSE and MSA versus M, while cholesterol biosynthesis was reciprocally increased (P < 0.05) 53.3 and 37.8% for MSE and MSA versus M, respectively. Cholesterol turnover was not influenced by diet. These data indicate that plant sterol and stanol esters differentially lower circulating total and LDL cholesterol levels by suppression of cholesterol absorption in hypercholesterolemic subjects.


Assuntos
Anticolesterolemiantes/farmacologia , Colesterol/sangue , Hipercolesterolemia/tratamento farmacológico , Lipídeos/sangue , Fitosteróis/farmacologia , Absorção , Adulto , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/química , LDL-Colesterol/sangue , Estudos Cross-Over , Método Duplo-Cego , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/dietoterapia , Cinética , Masculino , Margarina , Pessoa de Meia-Idade , Fitosteróis/administração & dosagem , Fitosteróis/química
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