title: The protective effect of α-Lipoic acid on mitochondria in the kidney of diabetic rats.
abstract: BACKGROUND
  Diabetic nephropathy (DN) is one of the most common chronic complications of diabetes and the leading cause of end-stage renal disease. Recent research has found that oxidative stress participates in the development of diabetic nephropathy. α-lipoic acid (α-LA), a powerful antioxidant, plays an important role in renal protection against DN, but the underlying mechanism remains unknown. This study modeled the renal protective effects of α-lipoic acid in streptozotocin (STZ) induced diabetic rats and explore the underlying mechanism, which provides new theoretical bases for clinical treatment of diabetic nephropathy.
  
  
  METHODS
  The diabetic model was induced by intraperitoneal injection of STZ on Male SD and then the diabetic rats were randomly divided into two groups: untreated-diabetic group (DM group), α-LA treated-diabetic group (α-LA group), and the normal rats served as control group (NC group). After 8 weeks of STZ induction, Blood glucose (BG), Blood Urea Nitrogen (BUN), Serum Creatinine (SCr) and urinary albumin excretion rate (UAER) were examined, and morphological changes were assessed by histology. The levels of malondialdehyde (MDA) and the activities of superoxide dismutase (SOD) were also evaluated in serum and renal cortex. Additionally, kidney mitochondrial membrane potential and mitochondrial swelling were measured for different groups. The expression of voltage-dependent anion channel (VDAC) on mitochondria were evaluated by both Western blotting and Immunohistochemistry.
  
  
  RESULTS
  After 8 weeks induction of STZ, significant reductions in BUN, SCr, UAER (P<0.01 or P<0.05) and histological improvement were observed in the α-LA group compared to the DM group. In the serum and renal cortex of α-LA group, the content of MDA and the activities of SOC were both significantly decreased (P<0.05). Compared to the DM group, the mitochondrial membrane potential in the α-LA group was significantly increased (P<0.05) and mitochondrial swelling was reduced. Meanwhile, the expression of VDAC on mitochondrial was significantly increased (P<0.05) in the α-LA group.
  
  
  CONCLUSIONS
  Our findings indicate that antioxidant α-LA exerts a protective role against the development of DN, and the underlying mechanism may involve effective suppression of the generation of oxidants, protection of mitochondrial function, and up-regulating of VDAC expression.
authors: Department of Endocrinology, The Affiliated People's Hospital of Jiangsu University Zhenjiang, Jiangsu 212002, China.
authors: Li
authors: L
authors: Wang
authors: Chen-Guang
authors: CG
authors: Wu
authors: Chun-Qian
authors: CQ
authors: Fang
authors: Jing
authors: J
authors: Gao
authors: Ying-Zhao
authors: YZ
authors: Liu
authors: Yan
authors: Y
authors: Chen
authors: Yu-Ning
authors: YN
authors: Chen
authors: Zhi-Gang
authors: ZG
authors: Xu
keywords: Diabetic nephropathy; mitochondria; reactive oxygen species; voltage-dependent anion channel; α-lipoic acid
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