Nerve Growth Factor-Conjugated Mesoporous Silica Nanoparticles Promote Neuron-Like PC12 Cell Proliferation and Neurite Growth

Therapeutic strategies to promote nerve cell growth and improve their functions or stimulate nerve fiber reconnection and ameliorate the loss of neuronal functions are in high demand. A disadvantage of current conventional methods, which includes injection of nerve growth factors (NGF) either systemically or in the affected area, is rapid clearance or degradation of NGF, thereby reducing the effective concentration of NGFs that can reach the damaged nerves to stimulate the healing process. To overcome this obstacle, a nanoparticle platform based on mesoporous silica nanoparticles (MSNs) was developed to not only prevent clearance and degradation of NGFs, but also deliver the NGF directly to nerve cells to promote nerve cell proliferation and neurite growth. We synthesized (NGF)-loaded MSN (MSN-NGF) with a diameter of 65 nm. MSN-NGF significantly promoted the differentiation of neuron-like PC12 cells and growth of neurites compared to NGF alone, as confirmed by MTS cell proliferation assay and optical microscopy analysis. This study shows that MSN-NGF could be an effective therapy to speed up nerve cell growth or recovery of function.