Diurnal variation in serum remnant-like lipoproteins, platelet aggregation and fibrinolysis in healthy volunteers.
Postprandial triglyceridemia and 'remnantemia' may better reflect the atherosclerotic risk than triglyceride (TG) levels in the fasting state. Recently, a new method was developed based on a monoclonal antibody recognizing an epitope distal to the carboxyl end of apo B48 which allows easy measurement of remnant-like lipoproteins (RLP). This study was performed in order to investigate RLP response to a standardized fat meal and establish a normal diurnal pattern of RLP in blood and compare it to platelet aggregation and fibrinolysis in healthy young men. We investigated 7 male volunteers (age range 18-23 years) who received a standardized fat meal (Othsuka Pharmaceutical Company, Japan) containing 32.9% lipids, 2.5% protein, 2.5% carbohydrate, 0.3% calcium and 0.1% phospholipids, and 74 mg/100 g cholesterol (C) at 7:30. The energetic value of this cocktail was 341 kcal/100 g. Area under curve (AUC) responses in TG, RLP-TG and RLP-C after the meal were as follows: for TG 28.66 +/- 8.94; for RLP-TG 17.54 +/- 5.55; for RLP-C 1.27 +/- 0.42 mg x dl-1 x h-1. These responses were correlated to each other. Surprisingly, collagen-induced platelet aggregation in whole blood was negatively related to RLP-C AUC. Fluctuation patterns of TG, RLP-TG and RLP-C concentrations during the day were remarkably similar, peaking in this particular group of subjects at 10:00-12:00 and at about 23:00, whereas cholesterol was decreasing late in the night and very early in the morning. This pattern was different from those of platelet aggregation and fibrinolysis parameters.
Rydzewski
A
A
2nd Department of Physiology, Hamamatsu University School of Medicine, Hamamatsu, Japan.
Urano
T
T
Nagai
N
N
Takada
Y
Y
Katoh-Oishi
Y
Y
Taminato
T
T
Yoshimi
T
T
Takada
A
A
D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D001053:Apolipoproteins / Q000097:blood*; D019540:Area Under Curve; D002784:Cholesterol / Q000097:blood; D002940:Circadian Rhythm / Q000502:physiology*; D004041:Dietary Fats / Q000008:administration & dosage; D005342:Fibrinolysis / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007564:Japan; D008074:Lipoproteins / Q000097:blood*; D008297:Male; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood; D010974:Platelet Aggregation / Q000502:physiology*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000097:blood; D014280:Triglycerides / Q000097:blood*
D001053:Apolipoproteins; D004041:Dietary Fats; D008074:Lipoproteins; D017395:Plasminogen Activator Inhibitor 1; D014280:Triglycerides; C112017:remnant-like particle cholesterol; D000324:Adrenocorticotropic Hormone; D002784:Cholesterol; D010959:Tissue Plasminogen Activator; D006854:Hydrocortisone