Search PubMedSearch

Biomedical subjects

B Jacotot

Publications and source records attributed to B Jacotot.

At least 19 recordsLinked to original sources

Long-term efficacy with fluvastatin as monotherapy and combined with cholestyramine (a 156-week multicenter study). French-Dutch Fluvastatin Study Group.

Fluvastatin monotherapy up to 40 mg/day over 52 weeks in patients with primary hypercholesterolemia decreased plasma low density lipoprotein cholesterol (LDL-C) by 28%, with varying decreases in plasma triglycerides and increases in high density lipoprotein cholesterol (HDL-C). Patients completing the 52-week study participated in a further trial to assess whether the efficacy of fluvastatin (20-40 mg/day), either as monotherapy or in combination with cholestyramine (CME; 4-16 g/day), taken at least 4 hours prior to fluvastatin, is sustained for up to 3 years. Patients were assessed every 12 weeks on average for safety and efficacy, the latter being calculated as a percent change from baseline of lipids or lipoproteins. During the second year (endpoint up to week 104), 147 patients received monotherapy (estimated mean dose, 30.2 mg/day) and 127 received additional CME (38.1 mg/day fluvastatin plus 10.1 g/day CME). During the third year (endpoint up to week 156), 140 patients received monotherapy (32.5 mg/day) and 67 received additional CME (39.3 mg/day fluvastatin plus 10.3 mg/day CME). Statistically significant reductions in mean total cholesterol and LDL-C and increases in mean HDL-C were achieved in both treatment groups and maintained throughout the study. A significant reduction in triglyceride levels was only observed at the second year endpoint in patients receiving monotherapy (-10.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Anticholesteremic Agents

Comparison of fluvastatin versus pravastatin treatment of primary hypercholesterolemia. French Fluvastatin Study Group.

Following a 6-week placebo period, 134 patients with low density lipoprotein cholesterol (LDL-C) > or = 160 mg/dL and plasma triglyceride < or = 400 mg/dL, despite following a standard lipid-lowering diet, were randomized to double-blind, double-placebo treatment with fluvastatin (22 women, 46 men; age 21-71 years) or pravastatin (25 women, 41 men; age 19-76 years). Fluvastatin at 40 mg and pravastatin at 20 mg were given for the first 4 weeks, both once daily with the evening meal. For the following 12 weeks, fluvastatin at 40 mg twice daily and pravastatin at 40 mg once daily were given with the evening meal. Both drugs were equally effective in lowering LDL-C after 4 weeks of treatment (-24.0% with fluvastatin, -24.1% with pravastatin) but, after 16 weeks, LDL-C reduction was -30.4% with fluvastatin and -26.6% with pravastatin. This further lowering of LDL-C between week 4 and week 16 was significant (p < 0.001) for fluvastatin but not pravastatin. Adverse events were reported by 23 fluvastatin patients and 22 pravastatin patients: 3 patients in each group withdrew from the study because of these. No notable abnormalities in levels of alanine or aspartate aminotransferase values (defined as > 3 times the upper limit of normal on 2 consecutive occasions) or of creatine phosphokinase (defined as > 10 times the upper limit of normal on any occasion) were observed in either treatment group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Effect of gemfibrozil on the concentration and composition of very low density and low density lipoprotein subfractions in hypertriglyceridemic patients.

The effect of gemfibrozil treatment on very low (VLDL) and low (LDL) density lipoprotein subfractions has been investigated in 9 moderate hypertriglyceridemic (HTG) patients (triglyceride (TG) levels 237-426 mg/dl). Three VLDL subfractions, VLDL1 (Sf 175-400), VLDL2 (Sf 100-175) and VLDL3 (Sf 20-100) and 4 LDL subspecies, LDL1 (1.023-1.028 g/ml), LDL2 (1.029-1.037 g/ml), LDL3 (1.038-1.049 g/ml) and LDL4 (1.050-1.062 g/ml) were prepared by density gradient ultracentrifugation. High density lipoprotein (HDL) chemical composition and lipolytic activities after heparin injection were also determined. Gemfibrozil induced a net decrease in VLDL1 and VLDL2 concentrations (P < 0.01). Cholesteryl ester (CE) weight percent was significantly reduced in both VLDL1 and VLDL2 subfractions. VLDL3 concentration and composition were not changed by the treatment. Lipoprotein lipase (LPL) activity was reduced in HTG patients (P < 0.05). After treatment, LPL activity increased (P < 0.05) but remained lower than in control, normotriglyceridemic (NTG) subjects. Furthermore, gemfibrozil increased HDL cholesterol (P < 0.05) and normalised the elevated HDL2 and HDL3 TG content. The increase of LDL cholesterol, often observed after gemfibrozil treatment, was due to a rise in the LDL2 subfraction (1.029 < d < 1.037 g/ml), the main fraction present in control subjects. However, despite the significant decrease of total plasma TG (329 mg/dl vs. 174 mg/dl), LDL3 subfraction (1.038 < d < 1.049 g/ml) was not reduced.

Adult

Effect of acute glycerol administration with or without a mixed meal in humans.

We explored the effects of oral glycerol administration (20 g) alone or in combination with a mixed meal on postprandial lipids, free fatty acids, high-density lipoprotein cholesterol and retinyl palmitate. We also tested the meal alone as a control. The metabolic behavior of 13C-labelled glycerol, mainly its incorporation into triglycerides and glucose, was also investigated. The tests were performed on 13 healthy subjects aged 20-56 years (mean 32.1 +/- 10.8). Glycerol administration alone induced a decrease in plasma free fatty acid levels. When glycerol was given with the meal, it was absorbed faster and postprandial triglyceride levels were higher compared to the meal alone (p < 0.05). An earlier and higher peak of retinyl palmitate was also observed when comparing the glycerol and mixed meal test to the mixed meal alone. No significant effect was observed on total, high-density and low-density lipoprotein cholesterol. These results suggest that the glycerol-induced increase in postprandial triglyceride levels is probably due to an increase in chylomicron synthesis and perhaps to the stimulation of intestinal glycerol kinase activity. 13C-labelled glycerol administration showed a more important glycerol incorporation in lipoproteins with a density range of < 1.006 during the test with glycerol alone as compared to the test with glycerol and a mixed meal, suggesting that the rate of glycerol incorporation into lipoproteins depends on the availability of other substrates.

Administration, Oral

Abnormal reverse cholesterol transport in controlled type II diabetic patients. Studies on fasting and postprandial LpA-I particles.

The high incidence and prevalence of coronary heart disease in diabetes mellitus is clearly established. The usual lipid pattern found in type II diabetic patients is a moderate increase in fasting triglyceride levels associated with low HDL cholesterol levels. These abnormalities are further amplified in the postprandial state. To study the effect of these alterations on reverse cholesterol transport, we isolated lipoprotein containing apoA-I but not apoA-II (LpA-I) particles by immunoaffinity chromatography from the plasma of well-controlled type II diabetic patients and nondiabetic matched control subjects. Different parameters involved in this antiatherogenic pathway were measured in both fasting and postprandial states. Diabetic patients had reduced levels of LpA-I particles that were protein enriched and phospholipid depleted. Gradient gel electrophoresis showed that control LpA-I particles had five distinct populations, whereas diabetic particles lacked the largest one. LpA-I isolated from diabetic plasma exhibited a decreased capacity to induce cholesterol efflux from Ob 1771 adipose cells both in fasting (15.1 +/- 10.0% versus 7.5 +/- 2.7%, P < .05) and postprandial (17.7 +/- 11.2% versus 7.7 +/- 3.9%, P < .05) states, whereas only control particles showed significantly higher ability to promote cholesterol efflux after the test meal (P = .02). Lecithin:cholesterol acyltransferase activity measured with an exogenous substrate showed a 54% increase and an 18% decrease postprandially for control subjects and patients, respectively. Thus, the different abnormalities found in the fasting state were further amplified in the postprandial situation. This resulted in LpA-I particles with aberrant size and composition and decreased ability to accomplish their antiatherogenic role in type II diabetic patients.

Adipose Tissue

Postprandial lipoprotein clearance in type 2 diabetes: fenofibrate effects.

Lipoprotein abnormalities [mainly high levels of very-low-density lipoprotein triglycerides (TG) and low levels of high-density lipoprotein cholesterol] increase the risk of cardiovascular disease in Type 2 diabetic patients. Moreover, only fasting TG and central obesity appear to independently predict mortality from CAD in glucose-intolerant and diabetic subjects. It is noteworthy that fasting lipid levels in these patients are often relatively unaffected, and that plasma TG may remain < 2 g/l, the cutoff point currently considered to define moderate hypertriglyceridemia. Our study of postprandial lipaemia shows that lipid intolerance (a greater increase of postprandial TG and a slower return towards basal levels) was almost always present in these patients, enabling us to detect atherogenic changes in plasma lipoproteins. Preliminary results indicate that fenofibrate treatment in Type 2 diabetes under optimised metabolic control improves not only fasting lipid levels but also postprandial lipaemia and associated abnormalities in lipoprotein levels and composition.

Diabetes Mellitus, Type 2

[Lipoprotein (a)].

Lipoprotein(a) or Lp(a) is similar to low density lipoproteins (LDL), but also contains a large glycoprotein molecule called apo-lipoprotein(a) or apo(a). The lipid composition of Lp(a) is nearly identical to that of LDL. The structure of apo(a) is similar to that of plasminogen. Several genetic polymorphisms have been described for apo(a). The increasing interest in Lp(a) is due to the positive correlation which exists between the plasma level of Lp(a) and the incidence of ischaemic heart disease. Plasma Lp(a) level varies greatly from one individual to another and is basically dependent on genetic factors, especially for the isoforms of apo(a). A level above 30 mg.dl is associated with increased risk of atherosclerosis-related diseases. There are few treatments which are effective in significantly reducing raised levels of Lp(a).

Cardiovascular Diseases

Long-term treatment of hypercholesterolemia with fluvastatin: a 52-week multicenter safety and efficacy study. French-Dutch Fluvastatin Study Group.

In this long-term (52-week) open-label extension to an earlier randomized, multicenter, double-blind, placebo-controlled, dose-finding trial, 381 patients with primary hypercholesterolemia received fluvastatin at increasing doses of 10 to 40 mg/day to achieve plasma low-density lipoprotein (LDL) cholesterol normalization, according to the European Atherosclerosis Society guidelines. The aim of the extension study was to assess the long-term efficacy, safety, and tolerability of fluvastatin. After 52 weeks of therapy, 75% of patients were receiving fluvastatin at 40 mg/day (mean dose: 36 +/- 8 mg/day). The mean percent change in LDL-cholesterol levels from baseline was -24.8% (p < 0.001), and 82.6% of patients achieved an LDL-cholesterol reduction of > or = 15%. In patients in the lowest baseline quintile, high-density lipoprotein-cholesterol levels were significantly (p < 0.001) increased by 8.8% whereas, in the highest baseline quintile, triglycerides were significantly (p < 0.001) reduced by 15.3%. Plasma lipoparticle (a) [Lp(a)]:B levels were also significantly reduced (-38.6%; p < 0.001). Fluvastatin was considered to be well tolerated by the majority of patients by both patients and investigators. The most frequently reported adverse event was abdominal pain. Notable biochemical abnormalities were rare. In conclusion, the results of this extension study indicate that fluvastatin at dosages of 20-40 mg/day is effective and well tolerated in patients with primary hypercholesterolemia and is accompanied by no particular problems of safety.

Adult

Postprandial amplification of lipoprotein abnormalities in controlled type II diabetic subjects: relationship to postprandial lipemia and C-peptide/glucagon levels.

Lipoprotein abnormalities, mainly high very-low-density lipoprotein (VLDL) and low high-density lipoprotein (HDL) levels, increase the risk of coronary heart disease (CHD) in type II diabetic patients. To investigate the relationship between these lipoprotein abnormalities and the postprandial (PP) lipid-clearing capacity, triglyceride (TG) and hormonal levels were determined hourly up to the 4th hour after a mixed meal containing 32.5 g lipids/m2 body surface in 14 treated non-obese type II diabetic patients with adequate nutritional and glycemic control (hemoglobin A1C [HbA1C] < 7%) and in 12 healthy subjects matched for age, sex, and body mass index (BMI). Mean cholesterol levels did not differ between patients and controls, with fasting TG moderately increased in diabetics (140 +/- 70 v 66 +/- 34 mg/dL, P < .01). Whereas fasting TG levels in patients showed a continuous distribution from 55 to 250 mg/dL, postprandial TG clearly identified two different subgroups. A "high-responder" or hypertriglyceridemic subgroup (HTG) showed PP TG levels significantly higher than control levels (290 +/- 62 v 106 +/- 41 mg/dL, P < .001), with higher fasting TG as well (181 +/- 52, P < .01), whereas both fasting and PP TG levels were not different from control levels in the normotriglyceridemic (NTG) diabetic subgroup. The magnitude of the PP triglyceridemic area showed a negative correlation with HDL2 cholesterol (r = .66, P < .001) and a positive correlation with PP HDL2 TG enrichment (r = .80, P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Asymptomatic homozygous hypobetalipoproteinemia associated with apolipoprotein B45.2.

Familial hypobetalipoproteinemia is caused by apolipoprotein (apo) B gene mutations and is frequently associated with a truncated apo-B protein in the plasma. Homozygosity for mutations yielding a truncated apo-B is extremely rare; fewer than five true homozygotes have been described in the world's literature. These patients typically have normal levels of triglycerides and virtually absent low density lipoprotein (LDL) cholesterol. The clinical status of these patients is variable, ranging from asymptomatic in two homozygotes who synthesized a truncated apo-B (apo-B87) to severe neurological disease resulting from vitamin E deficiency in a homozygote who synthesized a shorter apo-B (apo-B50). In this report, we describe a 48-year-old female homozygous for a nonsense mutation resulting in an even shorter apo-B, apo-B45.2. Although this individual had virtually no LDL cholesterol, she was asymptomatic and had normal plasma levels of vitamin E. This case demonstrates that homozygosity for an apo-B mutation associated with a relatively short apo-B truncation can be completely asymptomatic.

Alleles

Efficacy of a low dose-range of fluvastatin (XU 62-320) in the treatment of primary hypercholesterolaemia. A dose-response study in 431 patients. The French-Dutch Fluvastatin Study Group.

1. In this randomised, double-blind, placebo-controlled study, the efficacy of four dosages of fluvastatin (2.5, 5, 10 and 20 mg day-1) were assessed in 431 patients with primary hypercholesterolaemia recruited in 17 centres. 2. Following an 8-week dietary stabilisation phase and a 6-week placebo phase, the patients were randomised to receive placebo or fluvastatin 2.5, 5, 10 or 20 mg once daily at night for a period of 6 weeks. 3. Total cholesterol, beta-quant LDL-C, and the beta-quant LDL-C/HDL-C ratio were significantly reduced by all doses of fluvastatin, and HDL-C was significantly increased by the 10 mg and 20 mg doses. Fluvastatin 20 mg day-1 also significantly decreased TG and Lp(a):B levels. 4. Fluvastatin was well tolerated during the study, and relatively few biochemical or haematological abnormalities occurred. 5. Of the dosages tested, 20 mg fluvastatin day-1 is the optimal hypolipidaemic dose.

Adult

Familial xanthomatous hypercholesterolemia: abnormal exogenous lipid metabolism evidenced by the vitamin A test.

Familial xanthomatous hypercholesterolemia is a metabolic disorder associated with high LDL levels attributed to a familial defect in LDL receptor activity. We have previously shown that hyperlipoproteinemia of WHHL rabbits, considered to be a model for heritable hypercholesterolemia, was at least partly of exogenous origin. We have though studied retinyl palmitate (RP) levels 12 h after a standardized mixed meal as a simple test to detect abnormalities of intestinal-derived lipoprotein clearance in 22 familial hypercholesterolemic patients with xanthomatosis (13 of them treated by simvastatin, an HMGCoA reductase inhibitor, and 9 not treated), as compared to a control group (n = 12). Total and LDL cholesterol, plasma triglyceride and apo B levels were significantly higher in patients when compared to controls. Mean RP levels appeared higher in familial hypercholesterolemic patients, when compared to controls, with 6 among 22 patients showing clearly high vitamin A levels and 4 borderline values, whereas high triglyceride levels (> 2 g/l) were detected in only 1 patient. No patients within the group with high vitamin A levels showed an apo E2/E2 phenotype. Vitamin A levels correlated with plasma triglycerides in the whole group of subjects (r = 0.50, p < 0.05). No difference was observed in vitamin A distribution between treated and untreated hypercholesterolemic patients. Our results indicate that the clearance of RP-labeled intestinal lipoproteins is delayed in some xanthomatous familial hypercholesterolemic patients as compared with that of controls. These findings suggest that familial xanthomatous hypercholesterolemia may be heterogenous concerning physiopathological mechanisms inducing hyperlipidemia.

Adult

Effects of plasma lipid levels on blood distribution and pharmacokinetics of cyclosporin A.

The present study attempted to characterize the distribution of cyclosporin A (CsA) among the lipoprotein fractions, very-low-, intermediate-, low-, and high-density (VLDL, IDL, LDL, and HDL, respectively) in the plasma of patients awaiting heart transplantation and the influence of plasma lipid constituents on the pharmacokinetics of CsA. Major fractions of a therapeutic concentration of CsA were found in HDL and in LDL. In addition, plasma lipid concentrations (total cholesterol, triglycerides, phospholipids, VLDL-cholesterol--TC, TG, PL, VLDLc, respectively) are positively correlated with the CsA distribution within the LDL fraction, and negatively correlated with the CsA distribution within the HDL fraction. Thus, the percentage of CsA in each type of lipoproteins was shown to vary with the lipid levels among individuals. A significant negative correlation was found between apparent distribution volume at steady state (Vss) in plasma and TC, PL, and LDLc and between the area under the curve measured in blood (AUCB) for whole blood and PL.

Adult

Dietary monounsaturated fatty acids enhance cholesterol efflux from human fibroblasts. Relation to fluidity, phospholipid fatty acid composition, overall composition, and size of HDL3.

This study was designed to determine whether modifications induced by dietary fats on the high-density lipoprotein3 (HDL3) physicochemical characteristics could affect cholesterol efflux and intracellular cholesterol content, leading to upregulation of low-density lipoprotein (LDL) receptor activity from cultured fibroblasts. Serum HDL3S were obtained from 12 healthy women aged 26 to 49 years who adhered to four 7-week isocaloric diets containing 30% of the caloric intake as fat. Of the total calories, 15.6% of each diet was provided by (1) milk fats, rich in saturated fatty acids; (2) sunflower oil, rich in n-6 polyunsaturated fatty acids; (3) olive oil, rich in monounsaturated fatty acids; and (4) rapeseed oil, rich in n-3 polyunsaturated fatty acids. HDL3 isolated after the monounsaturated fatty acid diet induced the greatest cellular [3H]free cholesterol efflux, reduced the content of intracellular cholesterol, and enhanced 125I-LDL degradation. Univariate regression analyses suggested that the increased capacity of HDL3 to promote cellular [3H]free cholesterol efflux was in part due to its greater fluidity, higher cholesteryl ester content, elevated linoleic to linolenic acid ratio in phospholipids, and its smaller size. In conclusion dietary fats induced physicochemical changes in HDL3, which strongly modulated cellular cholesterol homeostasis in vitro. These data also suggest a novel mechanism by which dietary fats exert their effect on atherosclerosis.

Adult

Genetic and phenotypic heterogeneity in familial lecithin: cholesterol acyltransferase (LCAT) deficiency. Six newly identified defective alleles further contribute to the structural heterogeneity in this disease.

The presence of lecithin:cholesterol acyltransferase (LCAT) deficiency in six probands from five families originating from four different countries was confirmed by the absence or near absence of LCAT activity. Also, other invariate symptoms of LCAT deficiency, a significant increase of unesterified cholesterol in plasma lipoproteins and the reduction of plasma HDL-cholesterol to levels below one-tenth of normal, were present in all probands. In the probands from two families, no mass was detectable, while in others reduced amounts of LCAT mass indicated the presence of a functionally inactive protein. Sequence analysis identified homozygous missense or nonsense mutations in four probands. Two probands from one family both were found to be compound heterozygotes for a missense mutation and for a single base insertion causing a reading frame-shift. Subsequent family analyses were carried out using mutagenic primers for carrier identification. LCAT activity and LCAT mass in 23 genotypic heterozygotes were approximately half normal and clearly distinct from those of 20 unaffected family members. In the homozygous patients no obvious relationship between residual LCAT activity and the clinical phenotype was seen. The observation that the molecular defects in LCAT deficiency are dispersed in different regions of the enzyme suggests the existence of several functionally important structural domains in this enzyme.

Adolescent