Expression of Mitochondrial Respiratory Chain Complexes in the Vaginal Wall in Postmenopausal Women with Pelvic Organ Prolapse

Abstract

Background/Aims: Pelvic organ prolapse (POP) is a common disease affecting adult women. It is a result of the vaginal wall disorder as well as damage of the supportive structures contributing to the integrity of the pelvic floor. Mitochondrial disorders may have an important role in the vaginal wall degeneration leading to POP. The goal of this research is to examine if POP is associated with an altered expression of mitochondrial respiratory chain complexes. Methods: Samples of vaginal tissue were collected from 16 postmenopausal women: 10 had POP and 6 had other forms of benign gynecological disease. Using western blot, samples were analyzed to assess the expression of mitochondrial proteins including citrate synthase (CS), individual complexes of the mitochondrial respiratory chain and alpha smooth muscle actin (SMA). Results: A significantly reduced expression of SMA and complex II in vaginal tissue of women with POP was found, compared to the control group (p < 0.05), with a tendency for a reduced expression of CS (p = 0.06) and other complexes in the POP group. Conclusions: Our results indicate that there is a decreased quantity of the smooth muscle and a decreased expression of mitochondrial markers in the vaginal wall of women with prolapse suggesting their possible role in the pathogenesis of POP.