Application of multivariate analysis of TOF-SIMS spectra for studying the effect of high glucose intake on aortic lipid profile

Aim To study the effect of long-term glucose feeding on aortic lipid composition by using the time of flight-secondary ion mass spectrometry (TOF-SIMS). Method Rats were divided into two groups, drinking water with or without 10% glucose from birth to 6 months of age. The aortic wall was dissected out, high-pressure frozen, freeze-fractured, freeze-dried and analyzed by TOF-SIMS using a Bismuth cluster ion source. Surface spectra were taken from standardized regions of the vessel wall. Results Different peaks, such as cholesterol, fatty acids (FAs) and diacylglycerols (DAGs), were identified by the principal component analysis as carries of variance between two groups. These peaks were then compared by conventional t-test. Our data showed that the intensity of cholesterol, but not FAs and DAGs, was significantly decreased in the glucose-drinking rat. Moreover, the long-term glucose intake changed ratios between different FAs in the aorta. Conclusion The long-term glucose intake led to decreased cholesterol intensity in the aortic wall and this effect was revealed through a global analytical approach with objective selection of significant variables.