Osteoporosis Remission and New Bone Formation with Mesoporous Silica Nanoparticles.

Nanotechnology changed the concept of treatment for a variety of diseases, producing a huge impact regarding drug and gene delivery. Among the different targeted diseases, osteoporosis has devastating clinical and economic consequences. Since current osteoporosis treatments present several side effects, new treatment approaches are needed. Recently, the application of small interfering RNA (siRNA) has become a promising alternative. Wnt/β-catenin signaling pathway controls bone development and formation. This pathway is negatively regulated by sclerostin, which knock-down through siRNA application would potentially promote bone formation. However, the major bottleneck for siRNA-based treatments is the necessity of a delivery vector, bringing nanotechnology as a potential solution. Among the available nanocarriers, mesoporous silica nanoparticles (MSNs) have attracted great attention for intracellular delivery of siRNAs. The mesoporous structure of MSNs permits the delivery of siRNAs together with another biomolecule, achieving a combination therapy. Here, the effectiveness of a new potential osteoporosis treatment based on MSNs is evaluated. The proposed system is effective in delivering SOST siRNA and osteostatin through systemic injection to bone tissue. The nanoparticle administration produced an increase expression of osteogenic related genes improving the bone microarchitecture. The treated osteoporotic mice recovered values of a healthy situation approaching to osteoporosis remission.