title: Antioxidant activities of saponins extracted from Radix Trichosanthis: an in vivo and in vitro evaluation.
abstract: BACKGROUND
  Radix Trichosanthis (RT), the dry root tuber of Trichosanthis kirilowii Maxim (Cucurbitaceae), is a traditional Chinese medicine. Although a wide range of saponin pharmacological properties has been identified, to our knowledge, this may be the first report to investigate the crude saponins from RT. The purpose of this study was to delineate the antioxidant activity both in vitro and in vivo by using ethyl acetate (EtOAc), n-butanol, and the mixture of n-butanol and EtOAc fractions.
  
  
  METHODS
  In vitro antioxidant activity was detected by using DPPH free radical, hydrogen peroxide scavenging, and reducing power assays. After pretreatment with different fractions saponins at 2 mg/kg/d and 3 mg/kg/d of crude drug, respectively, an established CCl4 induced acute cytotoxicity model was used to evaluate the in vivo antioxidant potential by detection of superoxide dismutase (SOD), malonaldehyde (MDA), lactate dehydrogenase (LDH), and total antioxidant capacity (T-AOC) levels.
  
  
  RESULTS
  The in vitro assay showed that the antioxidant activity of all the three fractions was promising. The reducing power of the EtOAc and the mixture of n-butanol and EtOAc extracts increased in a dose dependent manner. However, both the n-butanol and the mixture of n-butanol and EtOAc fractions in low dose exhibited in a time dependent manner with prolonged reaction time. As for hydrogen peroxide scavenging capability, the n-butanol fraction mainly demonstrated a time dependent manner, whereas EtOAc fraction showed a dose dependent manner. However, in case of in vivo assay, an increase of SOD and T-AOC and decrease of MDA and LDH levels were only observed in n-butanol (2 mg/kg/d of crude drug) extracts pretreatment group.
  
  
  CONCLUSIONS
  RT saponins in n-butanol fraction might be a potential antioxidant candidate, as CCl4-induced oxidative stress has been found to be alleviated, which may be associated with the time dependent manner of n-butanol saponins in a low dose. Further studies will be needed to investigate the active individual components in n-butanol extract, in vivo antioxidant activities and antioxidant mechanisms.
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Pediatrics, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, China. myh1973@163.com.
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Miao
authors.forename: Liyong
authors.initials: L
authors.lastname: Huang
authors.forename: Juxiang
authors.initials: J
authors.lastname: Li
authors.forename: Haiyan
authors.initials: H
authors.lastname: Sun
authors.forename: Yuanzeng
authors.initials: Y
authors.lastname: Zhao
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Wenke
authors.initials: W
authors.lastname: Zhou
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology* / Q000633:toxicity; D002251:Carbon Tetrachloride / Q000633:toxicity; D056486:Chemical and Drug Induced Liver Injury / Q000209:etiology; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D051379:Mice; D018384:Oxidative Stress / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry*; D012503:Saponins / Q000494:pharmacology* / Q000633:toxicity
chemical_list: D000975:Antioxidants; D004365:Drugs, Chinese Herbal; D010936:Plant Extracts; D012503:Saponins; C034634:radix Trichosanthis; D002251:Carbon Tetrachloride; D007770:L-Lactate Dehydrogenase