HMOX1 and benign prostatic hyperplasia: However, BPH rats treated with O. majorana at doses of 250 and 500 mg/kg/day showed a significant increase in levels of protein of both Nrf2 and HO-1 antioxidant parameters compared to rats of both BPH and the finasteride groups as measured by ELISA immunoassay techniques (Figure 4A,B).