Estradiol-17ß [E2] stimulates wound healing in a 3D in vitro tissue-engineered vaginal wound model.

Childbirth contributes to common pelvic floor problems requiring reconstructive surgery in postmenopausal women. Our aim was to develop a tissue-engineered vaginal wound model to investigate wound healing and the contribution of estradiol to pelvic tissue repair. Partial thickness scalpel wounds were made in tissue models based on decellularized sheep vaginal matrices cultured with primary sheep vaginal epithelial cells and fibroblasts. Models were cultured at an airliquid interface (ALI) for 3 weeks with and without estradiol-17ß [E2]. Results showed that E2 significantly increased wound healing and epithelial maturation. Also, E2 led to collagen reorganization after only 14 days with collagen fibers more regularly aligned and compactly arranged Additionally, E2 significantly downregulated α-SMA expression which is involved in fibrotic tissue formation. This model allows one to investigate multiple steps in vaginal wound healing and could be a useful tool in developing therapies for improved tissue healing after reconstructive pelvic floor surgery.

A physiologically relevant, estradiol-17ß [E2]-responsive in vitro tissue-engineered model of the vaginal epithelium for vaginal tissue research.

AIMS: There are many situations where preclinical models of the human vagina would be valuable for in vitro studies into the pathophysiology of vaginally transmitted diseases, microbicide efficacy, irritability testing, and particularly, for assessing materials to be inserted in the vagina for support of the pelvic floor. The aim of this study is to develop a physiologically relevant, low cost, and ethically suitable model of the vagina using sheep vaginal tissue (SVT) to reduce the need for animal testing in gynecological research. METHODS: Tissue-engineered (TE) vaginal models were developed by culturing primary vaginal epithelial cells and vaginal fibroblasts, isolated from the native SVTs on decellularized sheep vaginal matrices at an air-liquid interface. Morphological analyses of the models were conducted by performing hematoxylin and eosin staining and further characterization was done by immunohistofluorescence (IHF) of structural proteins and cytokeratins. RESULTS: Histological analysis of the models revealed a gradual formation of a stratified epithelium on our decellularized matrices and cell metabolic activity remained high for 21 days as measured by the resazurin assay. Our models showed a dose-dependent response to estradiol-17ß [E2 ] with an increase in the vaginal epithelium thickness and cellular proliferation under higher E2 concentrations (100-400 pg/ml). The physiological relevance of these results was confirmed by the IHF analysis of Ki67, and cytokeratins 10 and 19 expression. CONCLUSION: In this study, we have developed an estradiol-responsive TE vaginal model that closely mimics the structural and physiological properties of the native SVT.

Demonstration of improved tissue integration and angiogenesis with an elastic, estradiol releasing polyurethane material designed for use in pelvic floor repair.

AIMS: Pelvic organ prolapse and stress urinary incontinence affect 40-50% of postmenopausal women worldwide. Polypropylene meshes have been extensively used for the surgical intervention of these disorders; however, these meshes can lead to severe complications in some patients. The need for synthetic materials more suited for use in pelvic floor repair is widely accepted. This study aims to develop an electrospun 17-ß-estradiol releasing polyurethane (PU) scaffold that not only provides the appropriate mechanical support but can also stimulate new extracellular matrix (ECM) production and angiogenesis. METHODS: PU scaffolds with and without 17-ß-estradiol (25 and 50 mg/g) were prepared by blend electrospinning. Mechanical properties of scaffolds were assessed by uniaxial cyclic and non-cyclic testing. The viability and ECM production of human adipose derived mesenchymal stem cells (hADMSCs) cultured on 17-ß-estradiol releasing PU scaffolds was evaluated. Angiogenic potential of estradiol releasing scaffolds was demonstrated by using an ex ovo chick chorioallantoic membrane (CAM) assay. RESULTS: The inclusion of estradiol in PU scaffolds did not change the ultrastructure but it significantly increased the ultimate tensile strength of scaffolds. hADMSCs on estradiol-releasing PU scaffolds showed more ECM production. The CAM assay revealed a significantly higher angiogenic potential of estradiol-releasing PU scaffolds with an additive effect seen when hADMSCs cultured on estradiol scaffolds. Histological examination of CAM tissue sections showed extensive cellular infiltration and a good tissue integration for all constructed scaffolds. CONCLUSIONS: This study shows the angiogenic potential of estradiol-releasing PU scaffolds with appropriate strength and elasticity desirable to support the pelvic floor.