Abstract:Objective: To explore the role of osteopontin (OPN) in inhibiting fibrosis after intrauterine adhesions (IUA) in mice. Methods: Primary bone marrow mesenchymal stem cells (MSCs) of C57 BL/6 mice and OPN-/-C57 BL/6 mice were isolated and cultured, and the surface antigens of separated cells were detected by flow cytometry. Thirty female mice were randomized into sham operation group, model group, OPN-/-MSCs group, MSCs group, and solvent group, with 6 mice in each group. One week after modeling, MSCs and OPN-/-MSCs were injected into the left and right uterine horns of the mice respectively. Two weeks after the treatment, two-dimensional ultrasound was conducted for the diagnosis of mouse uterus morphology, HE staining and Masson staining for the detection of the morphological changes and fibrosis of the endometrium of the uterus, immunohistochemical staining for the detection of the expression of α-smooth muscle actin (α-SMA), and Western blot for the detection of the protein expression of transforming growth factor-β1 (TGF-β1), vascular endothelial growth factor (VEGF), typeⅠcollagen α1 (COL1A1), and typeⅢcollagen α1 (COL3A1). Results: MSCs and OPN-/-MSCs cells were successfully isolated and cultured, and expression of CD29, CD44 and CD90 were positive and expression of CD34 was negative in both groups. Compared with the model group, the morphological changes of the uterus in the OPN-/-MSCs group and the MSCs group were improved, the number of glands increased in varying degrees, the area of fibrosis decreased, and the positive expression of α-SMA decreased significantly (P=0.000). TGF-β1, VEGF, COL1A1 and COL3A1 protein expression levels were significantly decreased (all P=0.000). Compared with the OPN-/-MSCs group, the uterine morphology of the MSCs group improved more markedly, the number of glands increased, and the area of fibrosis decreased, the positive expression of α-SMA decreased significantly (P=0.000), and the expression levels of TGF-β1, VEGF, COL1A1 and COL3A1 proteins also decreased significantly (all P=0.000). Conclusion: MSCs are more effective than OPN-/-MSCs in inhibiting intrauterine adhesions and endometrial fibrosis in mice, indicating that OPN has the effect of regulating bone marrow mesenchymal stem cells to inhibit endometrial fibrosis of intrauterine adhesions in mice.
