Effect of n-3 fatty acids on the composition and binding properties of lipoproteins in hypertriglyceridemic patients.
BACKGROUND
Treatment of hyperlipidemic patients with fish oil results in an increase in plasma LDL cholesterol despite a marked decrease in the LDL precursor, VLDL.


OBJECTIVE
We studied the relation between VLDL composition and LDL concentrations.


METHODS
Fourteen hypertriglyceridemic patients were treated with encapsulated fish oil (containing 1.45 g eicosapentaenoic acid and 1. 55 g docosahexaenoic acid/d) for 4 wk. Venous blood samples were collected before and after treatment. Eleven normolipidemic subjects served as a control group.


RESULTS
Fish oil effectively lowered plasma lipid and apolipoprotein (apo) E concentrations in the hypertriglyceridemic patients, whereas apo B concentrations increased. The lipid and apolipoprotein content of VLDL decreased, whereas LDL cholesterol and LDL apo B increased. Fractionation of VLDL by heparin-affinity chromatography showed that before treatment hypertriglyceridemic patients had more VLDL in the 0.05-mol NaCl/L subfraction and less in the 0.20-mol/L subfraction than did control subjects (P < 0.05), whereas the subfraction distribution pattern was normalized after fish-oil treatment. Nevertheless, plasma concentrations of the 0.05-mol NaCl/L subfraction were decreased and those of the 0.20-mol/L subfraction were increased in hypertriglyceridemic patients after fish-oil treatment (P < 0.05). Fish-oil treatment both enhanced VLDL binding and lowered LDL binding to fibroblasts.


CONCLUSIONS
Treatment of hypertriglyceridemic patients with fish oil caused differential effects on VLDL subfractions and decreased LDL binding to fibroblast receptors, which may have contributed to the paradoxical increase in LDL-cholesterol concentrations.
Hsu
H C
HC
Department of Internal Medicine (Cardiology), National Taiwan University Hospital, Taipei, Taiwan.
Lee
Y T
YT
Chen
M F
MF
D001055:Apolipoproteins B / Q000097:blood / Q000378:metabolism; D001667:Binding, Competitive; D015525:Fatty Acids, Omega-3 / Q000378:metabolism / Q000627:therapeutic use*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D015228:Hypertriglyceridemia / Q000188:drug therapy* / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000097:blood* / Q000378:metabolism; D008079:Lipoproteins, VLDL / Q000097:blood* / Q000378:metabolism; D008297:Male; D008875:Middle Aged
D001055:Apolipoproteins B; D015525:Fatty Acids, Omega-3; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL