retinol-palmitate and Coronary-Artery-Disease

Although a low plasma high-density lipoprotein cholesterol (HDL-C) level is a well-accepted risk factor for coronary artery disease (CAD), it is unclear whether pharmacologic agents can effectively increase HDL-C levels and/or reduce the incidence of CAD in patients with isolated low HDL-C levels. An important determinant of HDL levels is the efficiency of postprandial lipoprotein catabolism. The purpose of the present study was to evaluate the efficacy of bezafibrate therapy in increasing HDL-C levels in these patients and to examine its effect on postprandial lipoprotein levels. Fasting and postprandial lipid and lipoprotein levels were studied in 23 patients with isolated low HDL-C levels before and during 3 and 6 months of bezafibrate treatment. Postprandial lipoprotein levels were evaluated using the vitamin A-fat loading test, in which these intestinally derived lipoproteins are specifically labeled with retinyl palmitate (RP). Patients with isolated low HDL had significantly higher levels of chylomicron RP than a control group of 19 normolipidemic subjects. The area below the chylomicron RP curve was 17,773 +/- 6,821 versus 13,936 +/- 6,217 micrograms/L.h, respectively (P < .005). No differences were found in chylomicron remnant levels between the groups. Bezafibrate therapy reduced the chylomicron RP area by 27%, from 17,773 +/- 6,821 to 12,895 +/- 2,576, and the nonchylomicron RP area by 25%, from 6,059 +/- 3,310 to 4,430 +/- 1,963 (P < .0001). It increased fasting HDL-C levels from 35 +/- 3 to 38 +/- 1.4 mg/dL after 3 months (P < .001) and to 40 +/- 2.2 mg/dL after 6 months (P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aged; Bezafibrate; Cholesterol, HDL; Chylomicrons; Coronary Artery Disease; Coronary Disease; Diterpenes; Eating; Fasting; Humans; Hypolipidemic Agents; Hypolipoproteinemias; Lipoproteins; Male; Middle Aged; Retinyl Esters; Triglycerides; Vitamin A

To determine whether an increased familial risk for coronary artery disease in young adult men is related to changes in postprandial lipoprotein metabolism.. Cross-sectional study.. Coronary angiography departments of four central general hospitals in the Netherlands.. 80 sons (mean age, 24.8 years) of men with severe coronary artery disease and 55 sons (mean age, 23.2 years) of controls.. Postprandial levels of serum triglycerides, retinyl palmitate, and total cholesterol were measured during a 12-hour period after a standardized oral lipid load.. Both groups showed a marked increase in levels of serum triglyceride and retinyl palmitate after lipid loading, reaching a maximum 4 to 6 hours postprandially. No changes in postprandial total cholesterol levels were observed in either group. Sons of men with coronary artery disease had prolonged postprandial hypertriglyceridemia when compared with sons of controls. Significant differences in postprandial triglyceride levels were found at 8 hours (difference, 0.35 mmol/L; 95% CI, 0.07 to 0.62 mmol/L), at 10 hours (difference, 0.21 mmol/L; CI, 0.06 to 0.36 mmol/L), and at 12 hours after lipid loading (difference, 0.13 mmol/L; CI, 0.01 to 0.26 mmol/L). Levels of postprandial retinyl palmitate were also slightly, but not statistically, different (mainly after 6 hours).. Healthy young adult sons, whose fathers have established coronary artery disease, have prolonged postprandial hypertriglyceridemia. Changes in postprandial lipoprotein metabolism appear to be associated with familial risk for coronary atherosclerosis.

Topics: Adult; Coronary Artery Disease; Cross-Sectional Studies; Dietary Fats; Diterpenes; Eating; Humans; Lipids; Male; Nuclear Family; Retinyl Esters; Risk Factors; Time Factors; Triglycerides; Vitamin A

We investigated the metabolism of postprandial lipoproteins in four male patients who suffered from premature (less than 60 years) angiographically proven coronary heart disease. They had normal to low plasma total and low density lipoprotein cholesterol levels. Other risk factors were absent. Using the vitamin A fat loading test we were able to show that the clearance of chylomicron remnants was delayed compared to three healthy control subjects. It has been suggested that these postprandial lipoproteins may be atherogenic. Our data strongly favour the concept that defective removal of postprandial lipoproteins leads to the development of coronary heart disease in these patients.

Topics: Aged; Apolipoprotein E2; Apolipoproteins E; Cholesterol; Chylomicrons; Coronary Artery Disease; Dietary Fats; Diterpenes; Female; Half-Life; Humans; Lipoproteins; Male; Metabolic Clearance Rate; Middle Aged; Myocardial Infarction; Phenotype; Retinyl Esters; Risk Factors; Vitamin A

Topics: Cholesterol; Chylomicrons; Coronary Artery Disease; Dietary Fats; Diterpenes; Female; Fenofibrate; Humans; Hyperlipidemias; Lipoproteins; Male; Metabolic Clearance Rate; Middle Aged; Niacin; Retinyl Esters; Triglycerides; Vitamin A