ABSTRACT
During the human bone formation, the event of osteogenic differentiation of human bone mesenchymal stem cells (hBMSCs) is vital, and recent evidence has emphasized the important role of microRNAs (miRNAs) in osteogenic differentiation of hBMSCs. This study aims to examine the potential effects of miR-200c in osteogenic differentiation of hBMSCs and understand their underlying mechanisms. HBMSCs were obtained via human bone marrow. During osteogenic induction and differentiation, cells were transfected with different plasmids with the intention of investigating the roles of miR-200c on osteogenic differentiation, calcium salt deposition, alkaline-phosphatase (ALP) activity, mineralized nodule formation, osteocalcin (OCN) content, and proliferation of osteoblasts. Following transfection, dual luciferase reporter gene assay was conducted so as to explore the correlation between miR-200c and Myd88. Moreover, the AKT/ß-Catenin signaling pathway was blocked with an AKT/ß-Catenin inhibitor, AKTi, to investigate its involvement. The hBMSCs were successfully isolated from human bone marrow. Myd88 was determined as a target gene of miR-200c. Gain and loss-of-function assays confirmed that overexpression of miR-200c, or silencing of Myd88 promoted osteogenic differentiation, increased calcium salt deposition, ALP activity, mineralized nodule formation, and enhanced the proliferation of osteoblasts following osteogenic differentiation of hBMSCs. Meanwhile, the downregulation of miR-200c has been shown to have the opposite effect. Furthermore, these findings showed that the miR-200c overexpression activated the AKT/ß-Catenin signaling pathway by targeting Myd88. To sum up, the miR-200c upregulation induces osteogenic differentiation of hBMSCs by activating the AKT/ß-Catenin signaling pathway via the inhibition of Myd88, providing a target for treatment of bone repair.
Subject(s)
Cell Differentiation , Mesenchymal Stem Cells/enzymology , MicroRNAs/metabolism , Myeloid Differentiation Factor 88/metabolism , Osteogenesis , Pelvic Bones/enzymology , Proto-Oncogene Proteins c-akt/metabolism , beta Catenin/metabolism , Alkaline Phosphatase/metabolism , Calcium/metabolism , Cell Proliferation , Cells, Cultured , Gene Expression Regulation, Enzymologic , Humans , MicroRNAs/genetics , Myeloid Differentiation Factor 88/genetics , Osteocalcin/metabolism , Pelvic Bones/cytology , Proto-Oncogene Proteins c-akt/genetics , Signal Transduction , beta Catenin/geneticsABSTRACT
BACKGROUND: Genital prolapse is a debilitating manifestation of pelvic floor dysfunction. The cause of this condition has not been elucidated. The purpose of this study was to determine elastin content and RNA expression of related enzymes of elastin synthesis in uterosacral ligament biopsies from women with severe prolapse, and controls with normal pelvic support. METHODS: Biopsies were taken from the uterosacral ligament tissue of 31 women with Grade III or greater prolapse and 29 women with normal pelvic support. Elastin content was assessed by measuring desmosine using radioimmunoassay, and quantitative real time PCR was performed to quantify mRNA levels of lysyl oxidase (LOX), lysyl oxidase like-1 (LOXL1), LOXL2 and fibulin-5 (FIB-5). RESULTS: The mean desmosine concentration found in uterosacral ligaments of women with prolapse (n =26) was 103.3+/-59.3 pmolD/mgP compared to controls (n =29) 120.5+/-47.4 pmolD/mgP (p =0.1943). In the subgroup of subjects with complete procidentia (n =8), mean desmosine concentration was 50.6+/-25.8 and 127.1+/-42.2 pmolD/mgP in age-matched controls (n =12) (p <0.05). In tissue from subjects with more than 2 vaginal deliveries (n =18), the mean desmosine concentration was 99.9+/-60.7 and 133.0+/-44.0 pmolD/mgP in controls (n =17) (p <0.05). Expression of LOX, LOXL1 and LOXL2 decreased 8.2-fold+/-3.4, 5.0-fold+/-1.7 and 15.2-fold+/-5.2, respectively (mean+/-SD) in cases versus controls (p<0.05). Expression of FIB-5 was increased 3.1-fold+/-0.7 compared to controls (p<0.05). CONCLUSIONS: Significantly decreased desmosine content was measured in the uterosacral ligament tissue from women with prolapse versus controls in women with parity >2 and in women with complete procidentia. Suppression of mRNA for LOX and two LOX isoenzymes was correspondingly present. These results suggest that altered elastin metabolism is present in women with uterine prolapse.
Subject(s)
Elastin/deficiency , Uterine Prolapse/metabolism , Adult , Aged , Biopsy , Desmosine/metabolism , Elastin/biosynthesis , Elastin/metabolism , Extracellular Matrix Proteins/biosynthesis , Extracellular Matrix Proteins/genetics , Fascia/enzymology , Fascia/metabolism , Fascia/pathology , Female , Gene Expression , Humans , Isoenzymes , Ligaments/enzymology , Ligaments/metabolism , Ligaments/pathology , Middle Aged , Pelvic Bones/enzymology , Pelvic Bones/metabolism , Pelvic Bones/pathology , Protein-Lysine 6-Oxidase/biosynthesis , Protein-Lysine 6-Oxidase/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Uterine Prolapse/enzymology , Uterine Prolapse/genetics , Uterine Prolapse/pathologyABSTRACT
This article presents our experiences from fixation of the sacrum by transiliacal screw in 13 patients with unstable fractures of the pelvic ring. Early mobilization, with no secondary dislocation or postoperative complications, was achieved in all patients. Sagittal instability in unstable pelvic ring fractures must be acknowledged. The transiliac screw offers the possibility of early mobilization of patients with this fracture. The procedure is demanding and patients selected for this treatment should be referred to hospitals with experience in the treatment of pelvic fractures.
