Determinants of postprandial triglyceride and remnant-like lipoproteins in type 2 diabetes.
BACKGROUND
Postprandial changes in remnant-like lipoprotein particles (RLP) contribute to the severity of coronary heart disease in type 2 diabetes. Since the determinants of postprandial response in RLP are not well understood, this study investigated the roles of fasting triglyceride, apolipoprotein (apo) E polymorphism and insulin resistance in a group of overweight/obese Chinese type 2 diabetic subjects.


METHODS
Postprandial triglyceride (TG) and RLP-cholesterol (RLP-C) were determined after a mixed meal containing 70-g fat at 2-h intervals for 8 h in 32 normotriglyceridemic (NTG) and 31 hypertriglyceridemic (HTG) subjects. RLP-C was measured using an immunoseparation assay and apo E genotypes using polymerase chain reaction and restriction mapping. Insulin resistance was defined as homeostasis model assessment index (HOMA-IR).


RESULTS
The HTG subjects had greater postprandial increase in TG and RLP-C than NTG (p < 0.001), but there were no significant differences in HOMA-IR and apo E allele frequencies. Subjects who were non-E3-carriers had the largest postprandial increment in TG and RLP-C. On stepwise linear regression analysis, log(HOMA-IR) was only an independent determinant of fasting TG but not postprandial TG or RLP-C. The major determinants of fasting and postprandial RLP-C were fasting TG and apo E genotype, accounting for 53 and 6% of the variance of fasting RLP-C (p < 0.01) and 31 and 13% of the variance of postprandial RLP-C respectively (p < 0.01).


CONCLUSIONS
Insulin resistance is mainly a determinant of fasting triglyceride in Chinese type 2 diabetic subjects, whereas apo E genotype is a better predictor of both fasting and postprandial concentrations of RLP.
Tan
K C B
KC
Department of Medicine, University of Hong Kong, Hong Kong. kcbtan@hkucc.hku.hk
Tso
A W K
AW
Ma
O C K
OC
Pang
R W C
RW
Tam
S
S
Lam
K S L
KS
D000328:Adult; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000150:complications; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D015228:Hypertriglyceridemia / Q000097:blood* / Q000150:complications; D008055:Lipids / Q000097:blood; D008074:Lipoproteins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000097:blood*; D019518:Postprandial Period; D014280:Triglycerides / Q000097:blood*
D006442:Glycated Hemoglobin; D008055:Lipids; D008074:Lipoproteins; D010446:Peptide Fragments; D014280:Triglycerides