Plasma heavy metal levels correlate with deregulated gene expression of detoxifying enzymes in osteoporotic patients.

Heavy metal levels appear to be associated with low bone mineral density (BMD) and the consequent osteoporosis risk, but the relationship with the disease has not been clearly defined. The altered expression pattern of numerous genes, including detoxifying genes, seems to play a pivotal role in this context, leading to increased susceptibility to several diseases, including osteoporosis. The purpose of this study is to analyse circulating heavy metals levels and the expression of detoxifying genes in osteoporotic patients (OPs, n = 31), compared with healthy subjects (CTRs, n = 32). Heavy metals concentration in plasma samples was determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), and the subsequent expression analysis of NAD(P)H quinone dehydrogenase 1 (NQO1), Catalase (CAT), and Metallothionein 1E (MT1E) genes in Peripheral Blood Mononuclear Cells (PBMCs) was assessed by real-time polymerase chain reaction (qRT-PCR). Copper (Cu), mercury (Hg), molybdenum (Mo) and lead (Pb) were found to be significantly higher in the plasma of OPs compared to CTRs. Analysis of the expression levels of detoxifying genes showed a significant decrease in CAT and MT1E in OP group. In addition, Cu correlated positively with the expression levels of both CAT and MT1E in CTRs group and MT1E in OPs. This study shows an increased circulating concentration of certain metals combined with an altered expression pattern of detoxifying genes in OPs, highlighting a novel aspect to be investigated in order to better characterize the role of metals in the pathogenesis of osteoporosis.

Fracture liaison service model: project design and accreditation.

Frailty fractures place a significant socioeconomic burden on the health care system. The Italian Society of Orthopaedics and Traumatology (SIOT) is proceeding to fracture liaison service (FLS) model accreditation in several Italian Fracture Units (FUs), which provides a multidisciplinary approach for the management of the fragility fracture patient. INTRODUCTION: Osteoporosis and the resulting fragility fractures, particularly femoral fractures, place significant socioeconomic burdens on the health care system globally. In addition, there is a general lack of awareness of osteoporosis, resulting in underestimation of the associated risks and suboptimal treatment of the disease. The fracture liaison service (FLS) represents an exemplary model of post-fracture care that involves a multidisciplinary approach to the frail patient through the collaboration of multiple specialists. The purpose of this article is to highlight the path undertaken by the Italian Society of Orthopaedics and Traumatology (SIOT) for the purpose of certification of numerous FLS centers throughout Italy. METHODS: SIOT is proceeding with international FLS accreditation in several Italian Fracture Units (FUs), following the creation of a model that provides specific operational and procedural steps for the management of fragility fractures throughout the country. FUs that decide to join the project and implement this model within their facility are then audited by an ACCREDIA-accredited medical certification body. RESULTS: The drafted FLS model, thanks to the active involvement of a panel of experts appointed by SIOT, outlines a reference operational model that describes a fluid and articulated process that identifies the procedure of identification, description of diagnostic framing, and subsequent initiation of appropriate secondary prevention programs for fractures of individuals who have presented with a recent fragility fracture of the femur. CONCLUSION: Accreditation of this prevention model will enable many facilities to take advantage of this dedicated diagnostic-therapeutic pathway for the purpose of fracture prevention and reduction of associated health and social costs.

Clusterin silencing restores myoblasts viability and down modulates the inflammatory process in osteoporotic disease.

BACKGROUND: Targeting new molecular pathways leading to Osteoporosis (OP) and Osteoarthritis (OA) is a hot topic for drug discovery. Clusterin (CLU) is a glycoprotein involved in inflammation, proliferation, cell death, neoplastic disease, Alzheimer disease and aging. The present study focuses on the expression and the role of CLU in influencing the decrease of muscle mass and fiber senescence in OP-OA condition. METHODS: Vastus lateralis muscle biopsies were collected from 20 women with OP undergoing surgery for fragility hip fracture and 20 women undergoing arthroplasty for hip osteoarthritis. RESULTS: We found an overexpression of CLU in degenerated fibers in OP closely correlated with interleukin 6 (IL6) and histone H4 acetylation level. Conversely, in OA muscle tissues we observed a weak expression of CLU but no nuclear histone H4 acetylation. Ex vivo studies on isolated human myoblasts confirmed CLU overexpression in OP as compared to OA (p < 0.001). CLU treatment of isolated OP and OA myoblasts showed: modulation of proliferation, morphological changes, increase of histone H4 acetylation and induction of myogenin (MYOG) activation in OP myoblast only. In OP condition, functional knockdown of CLU by siRNA restores proliferative myoblasts capability and tissue damage repair, carried out by an evident upregulation of Transglutaminase 2 (TGM2). We also observed downmodulation of CX3CR1 expression with consequent impairing of the inflammatory infiltrate recruitment. CONCLUSIONS: Results obtained suggest a potential role of CLU in OP by influencing myoblasts terminal differentiation, epigenetic regulation of muscle cell differentiation and senescence. Moreover, CLU silencing points out its role in the modulation of tissue damage repair and inflammation, proposing it as a new diagnostic marker for muscle degeneration and a potential target for specific therapeutic intervention in OP related sarcopenia.