Studies on Fatty Acid Intake Patterns, Serum Lipids and Serum Fatty Acid Compositions of High School Students in Seoul / 대한지역사회영양학회지

The purpose of this study was to investigate the pattern of individual fatty acid intake and to compare serum lipid levels and total serum fatty acid composition of high school students in Seoul (total:234;male:91;female:143). In serum lipid levels, total cholesterol (Chol.), HDL -Chol. and LDL-Chol. levels of female students were significantly higher than those of male students and there was no significant difference between High Fish & Low Meat intake (HFLM) and Low Fish & High Meat intake (LFHM) groups. The average fat intake was 22 - 25 energy % of total subjects and especially, that of LFHM group was 29%, which were over the recommendation level. Although the average P/M/S ratio of dietary fat was 1.1/1.2/1.0, the average range of omega 6/omega 3 fatty acid ratio of dietary fat was found to be 17.9 - 20.7, which was far beyond the suggested range, 4 - 10. The average intake of cholesterol of total subjects was 360mg. LFHM group had more meats and beverages such as carbonated drinks and tended to have less beans, vegetables and mushrooms. In addition, LFHM group had more energy and fat intake than those of HFLM group, the P/S ratio of dietary fat (0.73) was lower than the recommended ratio. Serum C16:0 composition of LFHM group was significantly higher than that of HFLM group, and EPA and DHA composition of HFLM was significantly lower than that of LFHM. Therefore, in HFLM group, the P/S ratio of serum fatty acids was significantly higher and the omega 6/omega 3 ratio was lower. Dietary C18: 0 was negatively correlated with serum EPA and DHA composition. Individual PUFA intake was negatively correlated with serum C16:0 and sum of SFA, and positively correlated with serum C18:2omega 6 (LA), sum of omega 6 and sum of PUFA. Serum C18:1, C18:3omega 3 and C20:4omega 6 (AA) compositions were not correlated with dietary fatty acid. Only serum triglyceride (TG) levels were significantly correlated with serum fatty acid compositions. Sum of SFA, C14:0, C16:0, sum of MUFA and C18:1 compositions were positively correlated with serum TG levels, but LA, AA, sum of PUFA and P/S ratio were negatively correlated with it.

Effects of Short-Term Supplementation of Carnitine on Plasma and Urinary Carnitine and Plasma Lipid Levels of Healthy Male Adults

This study was conducted to evaluate changes in plasma concentration and urinary excretion of carnitine, as well as plasma lipid level and fatty acid composition, caused by short term supplementation of carnitine in humans. Ten healthy male subjects (21.2 +/- 0.5 years old) received oral carnitine supplementation (4 g/day) as tablets for two weeks. Fasting blood and random urine samples were collected from each subject both prior to and at the end of carnitine supplemention program. Following the 2 weeks of carnitine supplementation, plasma total carnitine (TCNE) concentration increased 20% (85.1 +/- 7.4 vs 67.3 +/- 9.1 micro mol/1, p>0.05), while urinary excretion of total carnitine increased ten times compared to the value measured prior to the supplementation (3051 +/- 692 vs 278 +/- 90.1 micro mol/g creatinine, p<0.01). Non-esterified carnitine (NEC) comprised from 71 to 88% of TCNE in plasma, and from 32 to 40% of TCNE excreted in the urine. Two weeks of carnitine supplementation in healthy adults significantly elevated plasma level of acid soluble acylcarnitine (ASAC) which is esterified mostly with short chain fatty acids (21.6 +/- 1.6 micro mol/l) compared to the value measured prior to the supplementation (6.4 +/- 0.8 micro mol/l) (p<0.05). Carnitine supplementation significantly increased plasma HDL-cholesterol level (p<0.05), and decreased the atherogenic index (p<0.05), but failed to cause any significant change in plasma levels of total cholesterol, triglyceride, and free fatty acids. Plasma triglyceride and phospholipid fatty acid compositions were not significaly affected as well by the oral supplementation of carnitine in subjects with normal range of blood lipid levels.

Effects of w3/ w6 fatty acids on behavioral developments of rats: Relation with neurotransmitters

Docosahexaenoic acid(DHA) is a major fatty acid of the gray matter in brain, especially of the synaptic membranes. Modification of membrane fatty acids by dietary fatty acids may influence membrane characteristics and metabolism of neurotransmitters including it's release and reuptake. The effect of w3/w6 fatty acids in maternal diet on the brain neurotransmitters of the offsptings and their behavioral development were investigated in this study. Adult female rats were fed experimental diets with different contents of w3 and w6 fatty acids throughtout pregnancy and lactation and up to 16weekss of pup's age. Experimental diets consisted of 10 wt% fat: cornoil (CO: source of w6, LA), perilla oil (PO: source of w3, a-LNA) and fish oil(FO: source of lonfg chain w3, EPA & DHA). At 3,7 and 16weeks of age, frontal cortex, corpus striatum, thaltmus and cerebellum were dissected out of the whole brain, and the concentrations of 5-hydroxytryptamines(5-HT), catechoamines,and their metabolites were measured by HPLC-ECD. At 16weeks of age, fatty acid compositions of whole brain were determined by GLC. Physical development test in Y-water maze were performed at 15weeks of pup's age. The concentrations of 5-HT in thalamus & hypothalamus was found to be most significiantly correlated with learning ability(r=0.508, p<0.05). At 15weeks of age, the PO group showed higher learning ability compared to the CO or the FO group. Evemn though the DHA level stays rather constant in thhe brain tissue, the ratios of arachidoni c acid(AA,w6)/EPA+DHA(w3) vary significiantly with dietary fatty acids. DHA is known to fulfill very important structural and/or metabolic funtion in membrane system of the brain and AA and its metabolites may also act as transsynaptic messenger and/or second messenger and as the substrate for the production of many biologically active compounds, such as prostaglandins. Therefore, to accomplish full development of brain, proper supply of AA as well as DHA must be considered. Much more studies are needed to clarify th.