The burden of osteoporosis (OP), and its accompanied low energy fractures, is ever increasing. Targeted therapies are under development to stem the tide of the disease, with microRNAs identified as biomarkers and potential targets. Assessing the functional capacity of bone marrow mesenchymal stromal cells (BMSC) from patients with low energy neck of femur fractures (NOF) will identify the expected outcomes to be achieved from new, targeted osteogenic therapies. Two patient groups were assessed; low energy NOF and osteoarthritic. Bone marrow aspirates were taken at time of arthroplasty surgery. The adherent fraction was cultured and assessed by flow cytometry, microRNA expression and differentiation functionality. Both patient groups demonstrated characteristic extracellular markers of BMSCs. 3 key markers were significantly reduced in their expression in the NOF group (CD 90, 13, 166 P=0.0286). Reduced differentiation capacity was observed in the NOF group when cultured in osteogenic and adipogenic culture medium. 105 microRNAs were seen to be significantly dysregulated, with microRNAs known to be crucial to osteogenesis and disease process such as osteoporosis abnormally expressed. This data demonstrates the impaired functional capacity of BMSCs and their abnormal microRNA expression in patients who suffer a low energy NOF. Future targeted therapies for OP must address this to maximise their restorative effect on diseased bone. The important role microRNAs can play as biomarkers and target sites has been further reinforced.
Osteoporosis is an international health and financial burden of ever increasing proportions. Current treatments limit the rate of bone resorption and reduce fracture risk, however they are often associated with significant and debilitating side effects. The most commonly used therapies also do not stimulate osteoblast activity 1,2,3. Much current research focus is aimed at the metabolic and epigenetic pathways involved in osteoporosis. MicroRNAs have been shown to play an important role in bone homeostasis and pathophysiological conditions of the musculoskeletal system. Up-regulation of specific microRNAs has been identified We have developed a 3D osteoporotic model from human bone marrow, without the use of scaffold. Magnetic nanoparticles are utilised to form spheroids, which provides a closer representation of the The results of initial monolayer and spheroid experiments will be presented. Optimisation of the osteoporotic bone marrow culture conditions, involving response to differentiation medias, analysis of adipose and bone markers and cell migration in spheroid culture will be displayed. Quantitative and qualitative results, including fluorescence microscopy and in cell western, assessing the monolayer and spheroid cultures will be presented. The development of a pseudo osteoporosis model from healthy bone marrow will also be discussed. This model will form a basis of future work on microRNA targeting. The development of improved therapies for osteoporosis is of great significance due to the predicted rise in incidence of the disease and associated fragility fractures. Targeted therapies, such as the manipulation of microRNA expression, offer the opportunity to increase osteoblastogenesis and decrease osteoclastogenesis, potentially without the associated side effects of older, systemic therapies. We believe our 3D human bone marrow derived osteoporotic model offers the closest relation to the
MiRNAs perform gene regulation that can target approximately 60% of human protein coding genes. Along with many cellular processes, miRNAs have been implicated in stem cell differentiation. Osterix (Osx), which is inhibited by mir-31, is required by MSCs for early osteoblast differentiation resulting in bone formation further downstream. We used antagomir functionalised gold nanoparticles (AuNPs) to block mir-31, which resulted in upregulation of Osx in pre-osteoblastic MG63 cells and human mesenchymal stem cells (MSCs). We used MG63 pre-osteoblastic cell line and human MSCs. Cytotoxicity of AuNPs was assessed by MTT, and cellular uptake of AuNPs was verified by TEM and ICP-MS. Osx RNA levels were determined by Fluidigm analysis and protein expression by In Cell Western analysis. Antagomir-functionalised AuNPs were incubated with cells for an initial 48 hours. (1) No cytotoxic effects were noted in either cell type. (2) Fluidigm analysis identified a varied gene response to antagomir delivery in both cell types, with MSCs recording a reduction of stem cell marker genes nestin, alcam, CD63, and CD44 at day 5 (indicating differentiation). (3) Osx protein levels were increased in both cell types after 48 hour incubation. (4) Downstream MSC analysis demonstrated accelerated osteogenesis at week 3 and 5 (verified by osteocalcin nodule formation) following 48 hour AuNP incubation. RNA analysis in both cell types suggested a shift away from proliferation towards osteoblastic differentiation. This was supported by Osx protein expression, which was increased in both MG63 cells and MSCs. Finally, an increase in the late osteogenic marker (osteocalcin) was verified at weeks 3 and 5 in MSCs after AuNP incubation for 48 hours. These results collectively infer successful delivery of mir-31 antagomirs, which are blocking mir-31-mediated suppression of Osx, resulting in an early increase in Osx, which accelerates MSC osteogenesis downstream.
Osteoporosis is an international health and financial burden of ever increasing proportions. Current treatments limit the rate of bone resorption and reduce fracture risk, however they are often associated with significant and debilitating side effects. The most commonly used therapies also do not stimulate osteoblast activity. Much current research focus is aimed at the metabolic and epigenetic pathways involved in osteoporosis. MicroRNAs have been shown to play an important role in bone homeostasis and pathophysiological conditions of the musculoskeletal system. Upregulation of specific microRNAs has been identified in-vivo in osteoporotic patients. It is hypothesized that modulation of specific mircoRNA expression may have a key role in future targeted therapies of musculoskeletal diseases. The assessment and analysis of their potential therapeutic use in Osteoporosis is of great importance, due to the burden of the disease. We have developed a 3D osteoporotic model from human bone marrow, without the use of scaffold. Magnetic nanoparticles are utilised to form spheroids, which provides a closer representation of the The results of initial monolayer and spheroid experiments will be presented. Optimisation of the osteoporotic bone marrow culture conditions, involving response to differentiation medias, analysis of adipose and bone markers and cell migration in spheroid culture will be displayed. Quantitative and qualitative results, including fluorescence microscopy and in cell western, assessing the monolayer and spheroid cultures will be presented. The development of a pseudo osteoporosis model from healthy bone marrow will also be discussed. This model will form a basis of future work on miRNA targeting.
Peninsula Spinal Unit, Princess Elizabeth Orthopaedic Centre, Royal Devon and Exeter Foundation NHS Trust, Exeter, UK. A retrospective audit in 2000 of cases presenting with metastatic cord compression (MSCC) was conducted. In June 2009 we introduced the role of MSCC coordinator. We present the preliminary results from a 6 month comparative audit and discuss whether implementation of the NICE Guidelines have improved the care pathway. Prospective cohort study with retrospective controlled group. Adults with suspected MSCC Length of time to MR imaging % referred for surgical opinion Length of time on bed rest. % undergoing surgery Retrospective audit 2000 38 cases confirmed MSCC. 11 did not have MRI and were treated on the basis of clinical symptoms. Average time from admission to MRI 42 hours. 8 patients (21%) referred for surgical opinion. None had surgery 38 had radiotherapy. Spinal stability documented on 1 patient. 5.5 days average bed rest Prospective audit 2009 54 patients referred to co-ordinator as suspected MSCC. 52 had MRI and 2 had CT. Average time from referral to MRI 41 hours. Average time for patients with neurological deficit 7.6 hours. 54 patients (100%) referred for surgical opinion. 12 patients had surgery (22%). 100% patients had spinal stability documented. Average length of time on bed rest 2 days. It is uncertain whether these results are attributed to the introduction of the NICE guidelines or improved awareness of condition. However we feel that NICE guidelines have improved the care pathway of patients with MSCC. Statement of ethics and interests: Study was approved and registered with audit department.
