Oleic acid to stearic acid ratio might be a potential marker for insulin resistance in non-obese Japanese

Analysis of the Correlation between Cholesterol Levels in Blood Using Clinical Data and Hair Using Mass Spectrometry Imaging

Mass spectrometry imaging (MSI) is a technique that visualizes the distribution of molecules by ionizing the components on the surface of a sample and directly detecting them. Previously, MSI using hair has primarily been used in the forensic field to detect illegal drugs. On the other hand, there are few examples of using this technology for health monitoring. In this study, hair and clinical data were collected from 24 subjects, and the correlation between blood cholesterol levels and cholesterol detected from cross-sectional hair slices was analyzed. As a result, a positive correlation with a correlation coefficient of 0.43 was observed between blood cholesterol and cholesterol detected from hair. Furthermore, when comparing the results of fluorescence staining (FS) of hair cholesterol with Filipin III and the MSI results, it was found that while FS could visualize detailed hair structures, there were cases where the results differed from MSI, possibly due to some cholesterol loss during the staining process. In the future, if various disease biomarkers can be detected using hair MSI, it could potentially become a non-invasive diagnostic method.

Estimated Elovl6 and delta-5 desaturase activities might represent potential markers for insulin resistance in Japanese adults

Purpose

Results from a recent study indicated that lower stearic acid/palmitic acid (SA/PA) and arachidonic acid/dihomo-γ-linolenic acid (AA/DGLA) ratios were associated with metabolically unhealthy obesity. However, this has not been extensively studied in the Japanese population.

Methods

We recruited 291 Japanese subjects with serum free fatty acid profiles undergoing health examinations. Whole serum desaturase activity was estimated as the product: precursor ratio -SA/PA ratio for elongation of long-chain fatty acid family member 6 (Elovl6) and AA/DGLA for delta-5 desaturase (D5D). The determinants of Elovl6 and D5D activity were investigated using multiple regression analyses.

Results

The Elovl6 and D5D activities exhibited a negative correlation with the logmatic-transformed TG/HDL-C ratio and TyG index. Multiple regression analyses revealed that the TG/HDL-C ratio and TyG index were negatively associated with Elovl6 and D5D activities. Most atherogenic markers were worse in the low Elovl6 or D5D activity group than in the high Elovl6 or D5D activity group. When study subjects were further stratified by TG levels, most atherogenic markers were the worst in the highest TG group in either the lowest Elovl6 or lowest D5D activity groups.

Conclusion

The estimated Elovl6 and D5D activities might be useful markers of insulin resistance in Japanese subjects.