| Content Provider |
World Health Organization (WHO)-Global Index Medicus |
| Author |
Lee, Joseph J. Lambert, Jennifer E. Hovhannisyan, Yelena Ramos-Roman, Maria A. Trombold, Justin R. Wagner, David A. Parks, Elizabeth J. |
| Description |
Author Affiliation: Lee JJ ( From the Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX (JJL, JEL, YH, and JRT)); Lambert JE ( From the Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX (JJL, JEL, YH, and JRT)); Hovhannisyan Y ( From the Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX (JJL, JEL, YH, and JRT)); Ramos-Roman MA ( From the Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX (JJL, JEL, YH, and JRT)); Trombold JR ( From the Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX (JJL, JEL, YH, and JRT)); Wagner DA ( From the Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX (JJL, JEL, YH, and JRT)); Parks EJ ( From the Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX (JJL, JEL, YH, and JRT)) |
| Abstract |
BACKGROUND: Biochemical evidence has linked the coordinate control of fatty acid (FA) synthesis with the activity of stearoyl-CoA desaturase-1 (SCD1). The ratio of 16:1n-7 to 16:0 [SCD116] in plasma triacylglycerol FA has been used as an index to reflect liver SCD116 activity and has been proposed as a biomarker of FA synthesis, although this use has not been validated by comparison with isotopically measured de novo lipogenesis (DNL(Meas)). OBJECTIVE: We investigated plasma lipid 16:1n-7 and FA indexes of elongation and desaturation in relation to lipogenesis. DESIGN: In this cross-sectional investigation of metabolism, 24 overweight adults, who were likely to have elevated DNL, consumed D2O for 10 d and had liver fat (LF) measured by magnetic resonance spectroscopy. Very-low-density lipoprotein (VLDL)-triacylglycerols and plasma free FA [nonesterified fatty acids (NEFAs)] were analyzed by using gas chromatography for the FA composition (molar percentage) and gas chromatography-mass spectrometry and gas chromatography-combustion isotope ratio mass spectrometry for deuterium enrichment. RESULTS: In all subjects, VLDL-triacylglycerol 16:1n-7 was significantly (P < 0.01) related to DNL(Meas) (r = 0.56), liver fat (r = 0.53), and adipose insulin resistance (r = 0.56); similar positive relations were shown with the SCD116 index, and the pattern in NEFAs echoed that of VLDL-triacylglycerols. Compared with subjects with low LF (3.1 ± 2.7%; n = 11), subjects with high LF (18.4 ± 3.6%; n = 13) exhibited a 45% higher VLDL-triacylglycerol 16:1n-7 molar percentage (P < 0.01), 16% of subjects had lower 18:2n-6 (P = 0.01), and 27% of subjects had higher DNL as assessed by using a published DNL index (ratio of 16:0 to 18:2n-6; P = 0.03), which was isotopically confirmed by DNL(Meas) (increased 2.5-fold; P < 0.01). Compared with 16:0 in the diet, the low amount of dietary 16:1n-7 in VLDL-triacylglycerols corresponded to a stronger signal of elevated DNL. CONCLUSION: The current data provide support for the use of the VLDL-triacylglycerol 16:1n-7 molar percentage as a biomarker for elevated liver fat when isotope use is not feasible; however, larger-scale confirmatory studies are needed. |
| File Format |
HTM / HTML |
| ISSN |
00029165 |
| e-ISSN |
19383207 |
| DOI |
10.3945/ajcn.114.092262 |
| Journal |
American Journal of Clinical Nutrition |
| Issue Number |
1 |
| Volume Number |
101 |
| Language |
English |
| Publisher |
American Society for Nutrition |
| Publisher Date |
2015-01-01 |
| Publisher Place |
United States |
| Access Restriction |
Open |
| Subject Keyword |
Discipline Nutritional Sciences Fatty Acids, Monounsaturated Blood Lipogenesis Lipoproteins, Vldl Liver Metabolism Non-alcoholic Fatty Liver Disease Triglycerides Up-regulation Adiposity Algorithms Biological Markers Body Mass Index Cross-sectional Studies Deuterium Oxide Diet, Fat-restricted Fatty Acids, Nonesterified Insulin Resistance Enzymology Diet Therapy Etiology Physiopathology Palmitic Acid Stearoyl-coa Desaturase Clinical Trial Research Support, N.i.h., Extramural |
| Content Type |
Text |
| Resource Type |
Article |
| Subject |
Nutrition and Dietetics Medicine |
