Name: THÁFANYS SOUSA TRAVEZANI
Publication date: 27/06/2024
Examining board:
Name |
Role |
|---|---|
| LUIS FELIPE DA CHAGAS E SILVA DE CARVALHO | Examinador Externo |
| ROGER LYRIO DOS SANTOS | Examinador Interno |
Summary: Menopause is a natural event that marks the end of the monthly sexual cycle and the reproductive phase in women. This process results in physical and hormonal changes, generating various symptoms and increasing the risk of disease onset. The alterations resulting from the decrease in circulating levels of female sex hormones can be investigated using an animal model of ovariectomy. Fourier transform infrared vibrational spectroscopy (FTIR) is a technique capable of extracting detailed molecular information and, as such, has been applied to various biological analyses. This study evaluated systemic changes in the ovariectomy model using mid-infrared spectroscopy. Thirty-eight serum samples from adult Wistar rats were analyzed, divided into 18 in the control group (SHAM) and 20 in the ovariectomized group (OVX). Bilateral ovariectomy was performed, followed by euthanasia of the rats after 15 days. Spectra collection was performed using the Bruker Alpha II equipment (Bruker, Germany), pre-processed, and analyzed using unsupervised analysis methods (Principal Component Analysis, PCA) and supervised analysis methods (Partial Least Squares Discriminant Analysis, PLS-DA) (MATLAB 2023). For the PCA model, combinations between principal components (PCs) 1 to 4 were performed. However, none of the PC combinations allowed a clear distinction between the OVX and SHAM groups. The PLS-DA model showed 66% sensitivity, 80% specificity, a false positive rate of 20%, and a false negative rate of 33%. The F-score was 0.727, and the accuracy was 72.7%. However, the y permutation test demonstrated that this result is random. These results indicate that there is no significant difference in the systemic profile of rats subjected to ovariectomy surgery for 15 days when analyzed using mid-infrared vibrational spectroscopy.
