Structural changes in amide I and amide II regions of PCOS women analyzed by ATR-FTIR spectroscopy

The etiology of PCOS is complex and frequently mis or undiagnosed, which may enhance morbidity and reduce the quality of life. Attenuated total reflection- Fourier transform infrared (ATR-FTIR) spectroscopy examines the structural fingerprints of the biochemical compounds and can provide distinct FTIR spectra of the PCOS cases and controls. The present study recruited 61 PCOS cases and 38 control women. The student's t-test was used to compare BMI, WHR, and lipid profile. The FTIR spectral region was compared among both groups using the Mann-Whitney U test and multivariate analysis involved principal component analysis (PCA) and hierarchical cluster analysis (HCA). FTIR spectra of different phenotypes of PCOS were also analyzed using multivariate analysis. In univariate analysis, PCOS women had significantly higher WHR (p = 0.007), BMI (p = 0.04), triglycerides (p = 0.04), and VLDL (p = 0.02) than the controls. The spectral regions of amide I (1700-1600 cm-1) and amide II (1580-1480 cm-1), were significantly greater in the PCOS group than in the controls (p < 0.01 and p < 0.001, respectively). The PCA and HCA revealed a distinct molecular fingerprint for phenotype A (PCOM + OA + HA) and phenotype B (HA + OA).<br /> Our study postulated that the spectral regions of amide I and amide II can distinguish between PCOS cases and control women and it may be used for the diagnosis of cases.