Vibrational characterization of granulosa cells from patients affected by unilateral ovarian endometriosis: New insights from infrared and Raman microspectroscopy

Endometriosis is a chronic gynaecological disease characterised by the presence of endometrial cells in extra-uterine regions. One of the main factors impacting on the fertility of women affected by endometriosis is the poor oocyte quality. Granulosa Cells (GCs) regulate oocyte development and maintain the appropriate microenvironment for the acquisition of its competence; hence, the dysregulation of these functions in GCs can lead to severe cellular damages also in oocytes. In this study, luteinized GCs samples were separately collected from both ovaries of women affected by Unilateral Ovarian Endometriosis and analysed by infrared and Raman microspectroscopy. The spectral data were compared with those of GCs from women with diagnosis of tubal, idiopathic or male infertility (taken as control group). The coupling of these two spectroscopic techniques sheds new light on the alteration induced by this pathology on GCs metabolism and biochemical composition. In fact, the study revealed similar biochemical modifications in GCs from both ovaries of women affected by unilateral ovarian endometriosis, such as the alteration of the protein pattern, the induction of oxidative stress mechanisms, and the deregulation of lipid and carbohydrate metabolisms. These evidences suggest that unilateral endometriosis impairs the overall ovarian functions, causing alterations not only in the ovary with endometriotic lesions but also in the contralateral "healthy" one.