Prolonged postprandial responses of lipids and apolipoproteins in triglyceride-rich lipoproteins of individuals expressing an apolipoprotein epsilon 4 allele.
Level 3 - non-randomized controlled study
Prospective non-randomized comparative cohort/physiological study stratified by genotype
PubMed 8550852 · doi:10.1172/JCI118408
What was done
Normolipidemic young men with either apo E3/3 or apo E4/3 phenotypes consumed a polyunsaturated fat-rich diet for 15 to 29 days. Investigators compared postabsorptive and postprandial responses (at 3 and 6 hours) of apo B48, B100, E, and lipids in triglyceride-rich lipoproteins (TRL) following a single test meal providing one-third of daily energy (39% fat calories).
What was found
Postabsorptive concentrations of TRL triglycerides, apo B48, and apo B100 were virtually identical between groups. Postprandially, TRL apo B48 peaked at 3 hours in both groups; at 6 hours, it returned to postabsorptive levels in the apo E3/3 group but remained 80% higher than baseline in the apo E4/3 group. TRL apo B100 also fell to baseline at 6 hours in the E3/3 group but remained 51% higher in the E4/3 group, closely coupled with TRL cholesterol and apo E.
Why it matters
These findings indicate that carrying an apo epsilon 4 allele impairs postprandial clearance of both intestinal-derived and liver-derived remnant lipoproteins, providing a potential mechanism for differential lipid metabolism and cardiovascular risk.
Limits
The abstract does not state the sample size. The study evaluated only young normolipidemic men under specific dietary conditions, limiting generalizability to women, older populations, and individuals with baseline dyslipidemia.
Cited by
- context Individuals who are APOE4-positive absorb dietary fat better than those who are APOE4-negative.