title: Protective effects of methanolic extract form fruits of Lycium ruthenicum Murr on 2,2'-azobis (2-amidinopropane) dihydrochloride-induced oxidative stress in LLC-PK1 cells.
abstract: BACKGROUND
  Fruits of Lycium ruthenicum Murr is a health food and also used as a folk to treat heart disease, abnormal menstruation and menopause in Tibetan, China. However; whether L. ruthenicum Murr fruits methanolic extracts (LFME) protect LLC-PK1 porcine renal tubules cells from AAPH-induced oxidative damage has not been investigated.
  
  
  OBJECTIVE
  To investigate the protective effects of L. ruthenicum Murr fruits methanolic extracts (LFME) against 2, 2'- azobis (2-amidinopropane) dihydrochloride (AAPH)-induced oxidative damage in renal proximal tubule LLC-PK1 cells.
  
  
  METHODS
  LLC-PK1 cells were co-incubated with AAPH (1mM) and different concentrations of LFMW together for 24 h. Cell viability was determined by MTT assay. Total intercellular reactive oxygen species (ROS) levels and lipid peroxidation were measured using a fluorescent probe 2', 7'-dichlorfluorescein-diacetate (DCFH-DA) and the TBA reactive substance (TBARS) assay, respectively. The endogenous antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-px) and intercellular glutathione (GSH) levels were determined using commercial assay kits according to the manufacturer's instructions.
  
  
  RESULTS
  LFME did not show a significant cytotoxic effect and increased the viability of LLC-PK1 cells in a concentration-dependent manner. LFME also decreased the total intercellular levels of ROS, reduced lipid peroxidation and increased the GSH levels as well as the activities of endogenous antioxidant enzymes to protect LLC-PK1 cells against AAPH-induced oxidative damage.
  
  
  CONCLUSIONS
  The results from the present study indicated that LFME is an effective ROS scavenger to protect LLC-PK1 cells against AAPH-induced oxidative damage through decreasing ROS generation, reducing lipid peroxidation and up-regulation of endogenous GSH levels and antioxidant enzymes.
authors.affiliation: Department of Nutrition and Food Hygiene, School of Public Health, Guilin Medical University, Guangxi 541004, People's Republic of China ; Department of Food Science and Nutrition, Pusan National University, Busan 609-735, South Korea.
authors.forename: Jia-Le
authors.initials: JL
authors.lastname: Song
authors.affiliation: Department of Pharmacy, Northern Jiangsu People's Hospital Affiliated to Yangzhou University (Clinical Medical College of Yangzhou University), Yangzhou, Jiangsu 225001, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Department of Pharmacy, Northern Jiangsu People's Hospital Affiliated to Yangzhou University (Clinical Medical College of Yangzhou University), Yangzhou, Jiangsu 225001, People's Republic of China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Xu
keywords: Antioxidant enzymes; LLC-PK1 cells; Lycium ruthenicum Murr; oxidative stress