APO-B SIGNAL PEPTIDE INSERTION DELETION POLYMORPHISM IS INVOLVED IN POSTPRANDIAL LIPOPARTICLES RESPONSES

The changes in postprandial concentrations of five lipoparticles (LpC- III, LpC-III:B, LpC-IIInoB, LpA-I and LpA-I:A-II) were studied on 144 apparently healthy (71 male and 73 female) subjects during the 4 h fol lowing the ingestion of a 1.260 kJ milkshake. The influence of apo B s ignal peptide polymorphism, apo E polymorphism, and other factors incl uding age, gender, BMI, tobacco and alcohol consumption on the postpra ndial responses of lipoparticles was investigated. Ape-A-I-containing lipoparticles were not influenced during the 4 h following the test me al except for LpA-I:A-II, which decreased in women. LpA-I:A-II is the only particle that showed a gender-dependent change in postprandial co ncentration. Apo-CIII-containing lipoparticles showed significant post prandial variations. Particles containing both apo B and apo C-III (to tal LpC-III and LpC-III:B), mainly present in VLDL fraction, had signi ficantly different postprandial responses among the genotypes of the a po B signal peptide polymorphism. Homozygotes for Dei allele showed a decrease of LpC-III:B concentrations over the 4 h, whereas Ins/Ins hom ozygotes and Ins/Del heterozygotes had a peak in concentration at 2 h. The apo B signal peptide polymorphism explained 2.3% of the variance of LpCIII:B, whereas apo E polymorphism did not influence the postpran dial concentrations of any lipoparticles.