NMR-Based Lipidomic Approach To Evaluate Controlled Dietary Intake of Lipids in Adipose Tissue of a Rat Mammary Tumor Model

摘要

The fatty acids composition of adipose tissue may provide information on the nutritional part of the risk or evolution of breast cancer. To determine whether H-1 NMR of adipose tissue provides information on the nature of the diet consumed, a dietary intervention with increasing percentage of polyunsaturated n-3 docosahexaenoic acid (DHA 22:6n-3, provided as DHASCO oil) was applied to a rat model of Nnitroso-N-methylurea-induced mammary tumors. Spectra of the lipid extracts were obtained from adipose tissues in five groups of Sprague Dawley rats fed with a diet containing 7% peanut/rapeseed enriched with 8% (w/w) of an oil without (palm oil) or with low (1%), moderate (3%), or high (8%) DHASCO content. A control group received a basal diet with 15% peanut/rapeseed representative of the "Western" diet. After 5 months of those five controlled diets, adipose tissue was collected for analysis of the lipid extract using both H-1 NMR analysis on an 11.7 T spectrometer and gas chromatography considered as gold standard. H-1 NMR analysis showed a dose-dependent increase in DHA in the lipid extract of adipose tissues and a commensurate decrease in n-6 polyunsaturated fatty acids in the three DHA groups, which allowed one to follow n-6-3 ratio changes. The highest n-6-3 ratio was observed in the control Western diet group compared to the other diet groups. The integrated spectral regions showed separation between groups, thereby documenting a specific NMR. lipid profile corresponding to each dietary intervention. Those diet-dependent NMR lipid profiles were consistent with that obtained with gas chromatography analyses of the same samples. This study is a proof of concept highlighting the potential use of the H-1 NMR approach to evaluate dietary intervention in biopsies of adipose tissues.