The main findings of the present study were as follows: (1) BPH was induced by injection of testosterone enanthate, and prostate weight was decreased as a result of the SE treatment; (2) oxidative stress in the serum and the prostate was increased by induction of BPH and was reduced by SE treatment; (3) expression of caspase-3, which is a measure of apoptosis, was increased in rats with BPH and decreased by the SE treatment; (4) the activity of 5-alpha-reductase was increased due to the induction of BPH but was decreased as a result of the SE supplementation. The gene discussed is CASP3; the disease is benign prostatic hyperplasia.