title: Mulberry leaf extract attenuates oxidative stress-mediated testosterone depletion in streptozotocin-induced diabetic rats.
abstract: BACKGROUND
  It has been proposed that oxidative stress may contribute to the development of testicular abnormalities in diabetes. Morus alba leaf extract (MAE) has hypoglycemic and antioxidant properties. We, therefore, explored the impact of the administration of MAE on steroidogenesis in diabetic rats.
  
  
  METHODS
  To address this hypothesis, we measured the serum level of glucose, insulin, and free testosterone (Ts) as well as oxidative stress parameters (including glutathione peroxidase, glutathione reductase, total antioxidant capacity, and malondialdehyde) in the testis of control, untreated and MAE-treated (1 g/day/kg) diabetic rats. In order to determine the likely mechanism of MAE action on Ts levels, we analyzed the quantitative mRNA expression level of the two key steroidogenic proteins, namely steroid acute regulatory protein (StAR) and P450 cholesterol side-chain cleavage enzyme (P450scc), by real-time PCR.
  
  
  RESULTS
  The MAE-treated diabetic rats had significantly decreased glucose levels and on the other hand increased insulin and free Ts levels than the untreated diabetic rats. In addition, the administration of MAE to the diabetic rats restored the oxidative stress parameters toward control. Induction of diabetes decreased testicular StAR mRNA expression by 66% and MAE treatment enhanced mRNA expression to the same level of the control group. However, the expression of P540scc was not significantly decreased in the diabetic group as compared to the control group.
  
  
  CONCLUSIONS
  Our findings indicated that MAE significantly increased Ts production in the diabetic rats, probably through the induction of StAR mRNA expression levels. Administration of MAE to experimental models of diabetes can effectively attenuate oxidative stress-mediated testosterone depletion.
authors.affiliation: Department of Biochemistry, Rafsanjan University of Medical Sciences, Rafsanjan, Iran;
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Hajizadeh
authors.affiliation: Molecular Medicine Research Center, Department of Biochemistry, Hormozgan University of Medical Sciences, Bandar Abbas, Iran;
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Eftekhar
authors.affiliation: Department of Reproductive Biology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran;
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Zal
authors.affiliation: Recombinant Protein Laboratory, Department of Biochemistry, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran;
authors.forename: Aida
authors.initials: A
authors.lastname: Jafarian
authors.affiliation: Recombinant Protein Laboratory, Department of Biochemistry, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran; ; Maternal-Fetal Medicine Research Center, Hafez Hospital, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Mostafavi-Pour
keywords: Diabetes mellitus; Morus alba; Oxidative stress; Testosterone