['Infertility is a common complication in diabetic men and experimental animals, mainly due to loss of germ cells by apoptotic cell death. The aim of this study was to evaluate the effects of aqueous and ethanol extracts of Dracaena arborea in streptozotocin-induced ultra-structural spermatogenic alterations in Wistar rats.', 'Diabetic animals were orally treated with Millipore water (10\u2009ml/kg), sildenafil citrate (1.44\u2009mg/kg) or Dracaena arborea aqueous (500\u2009mg/kg) and ethanol (100\u2009mg/kg) extracts for three weeks. A group of non diabetic rats received Millipore water (10\u2009ml/kg) and served as healthy control group. Blood glucose was monitored at the beginning and the end of the study. One day after the last treatment, animals were sacrificed and the testes immediately removed were morphologically observed and prepared for electron microscopy analysis of spermatogenesis.', 'Our results showed that Dracaena arborea was devoid of any anti-hyperglycemic activity. In the untreated diabetic rats, hyperglycemia severely damaged the testes morphology as well as the spermatogenic process as evidenced by the: thickness of basement membrane of the seminiferous tubule; mitochondria alteration; abnormal spermatocyte cells displaying polymorphous nuclei, cytoplasmic vacuolization and necrosis; and disorganization and degeneration of sperm germ cells. Administration of sildenafil citrate and Dracaena arborea extracts to the diabetic rats improved testes morphology and reversed, although not completely, the impairment of spermatogenesis; this alleviating effect was more pronounced in animals treated with the aqueous extract (500\u2009mg/kg) of Dracaena arborea.'] Does dracaena arborea alleviate ultra-structural spermatogenic alterations in streptozotocin-induced diabetic rats?