title: Quantification of lipoprotein X and its relationship to plasma lipid profile during different types of parenteral nutrition.
abstract: An abnormal lipoprotein (LP), detected in plasma during total parenteral nutrition, has been shown to be similar to LPX observed in cholestasis and in familial lecithin-cholesterol-acyl-transferase (LCAT) deficiency. However, the conditions which facilitate the appearance of LPX during total parenteral nutrition are unclear; potential determining factors could be lipid input, plasma lipid levels, and/or inhibition of LCAT activity. An investigation was conducted on 12 patients receiving total parenteral nutrition for 3 wk by simultaneously evaluating plasma LPX (via a quantitative method) as well as total cholesterol, phospholipids (PL), triglycerides (TG), apolipoprotein B, and LCAT activity. Daily total nonprotein calories (40 kcal/kg body weight) and nitrogen input (250 mg/kg body weight) were fixed in this study. Three 7-day periods were defined: during periods 1 and 3, lipid emulsion (10 or 20% Intralipid) and glucose were given as nonprotein calories (glucose-lipid periods); in period 2, glucose was administered alone as the sole source of nonprotein energy (glucose period) so that the total energy input was not modified. During periods 1 and 3, the patients were randomly assigned to receive either 9 g (period 1) and 12 g (period 3) of PL/day for 7 days, or 12 and 9 g of PL/day. By infusing either 10 or 20% Intralipid, TG input was varied concomitantly so that the subjects received 75, 100, or 150 g/day in periods 1 and 3. During the glucose-lipid periods, plasma LPX was measurable from the 2nd day and increased progressively. Its increment was closely related to a rise in unesterified cholesterol and PL (r = 0.7; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000328:Adult; D000368:Aged; D002784:Cholesterol / Q000097:blood; D005217:Fat Emulsions, Intravenous / Q000008:administration & dosage*; D005260:Female; D005947:Glucose / Q000008:administration & dosage; D006801:Humans; D008073:Lipoprotein-X / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010288:Parenteral Nutrition / Q000379:methods; D010289:Parenteral Nutrition, Total / Q000379:methods; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000097:blood; D010743:Phospholipids / Q000097:blood; D010949:Plasma / Q000032:analysis; D014280:Triglycerides / Q000097:blood
chemical_list: D005217:Fat Emulsions, Intravenous; D008073:Lipoprotein-X; D010743:Phospholipids; D014280:Triglycerides; D002784:Cholesterol; D007862:Phosphatidylcholine-Sterol O-Acyltransferase; D005947:Glucose