LOXL1 deficiency negatively impacts the biomechanical properties of the mouse vagina and supportive tissues

Mice deficient in lysyl oxidase-like1 protein (LOXL1(-/-)) develop pelvic organ prolapse (POP). We sought to determine the impact of LOXL1(-/-) on the biomechanical properties of the vagina and its supportive tissues tested as a complex. Tissues of nulliparous LOXL1(-/-) and age-matched wild type (WT) mice were tested to failure to obtain load-distension curves. Data were compared utilizing one-way analysis of variance and appropriate post hoc tests. The groups demonstrated different biomechanical behavior, with LOXL1(-/-) animals displaying a 31% decrease in ultimate load at failure (p=0.001). Experimental disruption of specific levels of support in WT mice failed to generate load-distension curves similar to the LOXL1(-/-) mice indicating a global instead of a site-specific tissue defect. The decrease in the ultimate load at failure in the LOXL1(-/-) mice suggests mechanically weaker tissues. LOXL1 mutation results in a global defect in connective tissues and correlates with altered biomechanical behavior of the vagina and supportive tissues.