Stromal Derived Factor-1 (SDF-1) is a small, naturally occurring, potent chemokine with inherent angiogenic, neurogenic, anti-apoptotic protein, which is also a potent stem cell chemoattractant, cardiovascular disease, and other metabolic disturbances. The present invention provides methods for treating erectile dysfunction in a male subject comprising administering to the major pelvic ganglion supplying the cavernous nerves subject compositions comprising SDF-1. SDF-1 promotes stem cell activation, to the major pelvic ganglion supplying the cavernous nerves, helps cell preservation, and prevents adverse penile remodeling. It can be administered as a protein or by gene therapy including but not limited to plasmid DNA, viral transduction, or nanoparticle delivery directly to the penis or to the neurovascular bundle or other pelvic nerve structures during the time of surgery, or before injury, or to treat existing erectile dysfunction.