Low copy number and high 4977 deletion of mitochondrial DNA in uterosacral ligaments are associated with pelvic organ prolapse progression

Introduction and hypothesis: The pathophysiology of pelvic organ prolapse (POP) is related to aging in the pelvic organ support, and mitochondrial dysfunction is one of the major contributors to aging. Therefore, the objective of this study was to investigate the correlation between alternations of mitochondrial DNA and progression of POP. Methods: Polymerase chain reaction (PCR) was applied in the present study. Uterosacral ligaments (UL) were obtained from 45 POP patients and 38 myoma patients without POP. Chi-square test, Student's t-test, Mann-Whitney U test, and Spearman correlation analysis were applied in the comparison between POP and non-POP patients. Results: The results revealed that significant depletion of mitochondrial DNA (mtDNA) and an increase in the incidence of 4977 deletion of mtDNA (mtDNA⁴⁹⁷⁷) in the UL tissue of POP patients. Conclusions: The alternations of mtDNA may play an important role in the molecular pathogenesis and process of POP formation.