title: Rapid but mild genoprotective effect on lymphocytic DNA with Panax notoginseng extract supplementation.
abstract: BACKGROUND
  Panax notoginseng (PN) is a well-known Chinese medicinal herb traditionally used as a hemostatic agent that strengthens and builds blood. The free radicals scavenging and antioxidant property of PN have been demonstrated in various studies either in vitro or in animal models, however, the genoprotective effect at human cellular level remains to be elucidated.
  
  
  OBJECTIVE
  The current supplementation study aimed to investigate the genoprotective effect of PN. The study explored the DNA protection effect after a single dose of 2500 mg commercial notoginseng extract in water.
  
  
  METHODS
  Six subjects, (3 males, 3 females) were recruited and each attended two trials. In the first trial, pre-ingestion and 2 hour-post-ingestion blood samples were collected and they were challenged with 50 µM H2O2. In the second trial, water was taken instead as control. Lymphocytes with or without challenge were then subjected to comet assay. DNA damage was assessed under fluorescent microscope.
  
  
  RESULTS
  Results showed a significant (P < 0.05) but mild decrease (3%) in the comet score after PN supplementation, indicating that PN supplementation reduces the H2O2-induced DNA damage in the lymphocytes and enhanced their resistance to oxidative damage giving a mild acute genoprotective effect against oxidant challenge. No change of comet score was observed in control trial.
authors.affiliation: Department of Applied Science, Hong Kong Institute of Vocational Education (Shatin), Hong Kong, China ; Macao Society for the Study of Women's Health, Macao, China.
authors.forename: Yim Tong
authors.initials: YT
authors.lastname: Szeto
authors.affiliation: Department of Pathology, Tseung Kwan O Hospital, Hong Kong, China.
authors.forename: Loretta Kit Yee
authors.initials: LK
authors.lastname: Lee
keywords: Antioxidant; comet assay; hydrogen peroxide; pseudoginseng; supplementation