Changes in serum and lipoprotein fatty acids of growing rats fed protein-deficient diets with low or adequate linolenic acid concentrations.
The effects of a protein-deficient diet associated with sunflower oil [adequate in 18:2(n-6), poor in 18:3(n-3)] or soybean oil [adequate in both 18:2(n-6) and 18:3(n-3)] on lipid serum and lipoprotein compositions were studied in growing rats. Four groups of rats were fed different diets: SFC (20% casein + 5% sunflower oil); SFd (2% casein + 5% sunflower oil); SC (20% casein + 5% soybean oil); Sd (2% casein + 5% soybean oil). After 28 d, both protein-deficient groups exhibited low concentrations of protein, phospholipid, triacylglycerol and total cholesterol in serum and VLDL. Compared with rats fed 20% casein diets, those fed low protein diets had lower 18:2(n-6) and 20:4(n-6) in phospholipids of serum, VLDL and HDL2-3, and the 20:4(n-6)/18:2(n-6) ratio was twofold higher in triacylglycerols of serum and VLDL. In the SFd-fed group, 22:5(n-6) was higher than in the SFC-fed group for both triacylglycerols and phospholipids in overall lipoprotein fractions studied. In addition, the 20:3(n-9)/20:4(n-6) ratio was 0.1 in HDL2-3 phospholipids of the SFd-fed group. Sunflower oil-fed rats compared with soybean oil-fed rats had greater monounsaturated fatty acids and lower total (n-3) fatty acids in both triacylglycerols and phospholipids of serum, VLDL and HDL2-3, as well as lower total (n-6) fatty acids in serum and VLDL triacylglycerols. Apolipoproteins (apo) of VLDL were drastically depressed in rats fed protein-deficient diets, whereas apo-AI of HDL2-3 showed a particular resistance. Likewise, sunflower oil-fed rats had enhanced apo-B48 of VLDL and apo-C, apo-AII and apo-AIV of HDL2-3. The present findings show that some effects of protein malnutrition were enhanced by alpha-linolenic acid deficiency, in particular reduced (n-6) and (n-3) fatty acid bioavailability.
Bouziane
M
M
Unité de Recherches de Nutrition Cellulaire et Métabolique, Université de Bourgogne, Faculté des Sciences Mirande, Dijon, France.
Prost
J
J
Belleville
J
J
D000818:Animals; D005227:Fatty Acids / Q000032:analysis / Q000097:blood*; D006368:Helianthus; D008042:Linolenic Acids / Q000008:administration & dosage / Q000172:deficiency*; D008074:Lipoproteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D008075:Lipoproteins, HDL / Q000032:analysis; D008079:Lipoproteins, VLDL / Q000032:analysis; D008297:Male; D010743:Phospholipids / Q000097:blood / Q000737:chemistry; D011488:Protein Deficiency / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains / Q000254:growth & development; D013025:Glycine max; D014280:Triglycerides / Q000097:blood / Q000737:chemistry
D005227:Fatty Acids; D008042:Linolenic Acids; D008074:Lipoproteins; D008075:Lipoproteins, HDL; D008079:Lipoproteins, VLDL; D010743:Phospholipids; D014280:Triglycerides