Bo-controlled clinical trial in healthy subjects to evaluate the effects of KRG supplementation on biomarkers of oxidative stress and lipid peroxidation, which included lymphocyte DNA damage, urinary 8-epiprostaglandin F2 (PGF2), plasma oxidized low-density lipoprotein (LDL), and antioxidant enzymes.MethodsSubjectsSixty-nine healthy subjects (aged 20?5 years) were recruited during routine check-ups at a health promotion center at Yonsei University Hospital from May to November in 2009. Participants were asked to visit four times (1 week before and at 0, 4, and 8 weeks). Blood samples were taken at weeks 0 and 8, and diet and capsule intakes were assessed at weeks 0, 4, and 8. Healthy subjects who either used cigarettes or consumed alcohol (or both) were enrolled in this study at the Laboratory of Clinical Nutrigenetics/Nutrigenomics at Yonsei University. The exclusion criteria were the consumption of more than three servings of vegetables or fruit per day, antioxidant or vitamin/mineral supplementation, history of chronic disease (e.g., diabetes, heart disease, renal disease), or the use of medication (e.g., lipid-lowering or antihypertensive medications, anti-platelets, or diseaserelated medications). The participants were interviewed to determine their smoking and drinking habits. Smoking status was categorized as “current smoker” or “nonsmoker,” and alcohol consumption was categorized as “current drinker” or “nondrinker.” Nonsmokers or nondrinkers included both ex-consumers and those who had never consumed. Ex-smokers and ex-drinkers were defined as subjects who stopped smoking or drinking at least 1 year prior to participating in the study. Current smokers were asked the number of cigarettes smoked per day. Current drinkers were asked about the type and amount of alcohol consumed per day, and the amount of alcohol was then calculated as grams per day. The study subjects number calculation assumed a twotailed alpha = 0.05 and 1- = 90 to detect a 10 difference with a standard error of 0.28 in the comet assay which is primary outcome and an attrition rate (20 ). Biomarkers for testing antioxidant/oxidative effects and the number of subjects were determined by following the criteria recommended by the Korea Food and Drug Administration. Of the 69 study subjects, 12 subjects (placebo group, n = 4; low-dose group [3 g KRG/day], n = 4; high-dose group, [6 g KRG/day], n = 4) discontinued the study for personal reasons. No adverse reactions (e.g., fever, hot flush, nausea, vomiting, diarrhea) due to KRG supplementation were observed among the 57 subjects who completed the study.Kim et al. PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/27488460 Nutrition Journal 2012, 11:47 http://www.nutritionj.com/content/11/1/Page 3 ofTest capsule and study designIdentical-looking capsules contained red ginseng (low dose, 300 mg; high dose, 600 mg) or placebo (300 mg of KRG-flavored capsule containing corn starch). Red ginseng and placebo capsules were provided by the Korea Ginseng Cooperation (KGC, Daejeon, Korea). The red ginseng contained 16.58 mg/g total ginsenosides, and the ratio of protopanaxadiol ginsenosides (Rb1, Rb2, Rc, Rd, and Rg3) to FCCP site protopanaxatriol ginsenosides (Rg1, Re, and Rf ) was 1.65. Analyses of common ginsenosides were performed in quadruplicate using standard HPLCUV techniques [14] at the Korean Ginseng Research Institute in Daejeon, Korea. This study design was the randomized double-blind, placebo-controlled intervention trial for 8 week and was approved by the Institutional Review Bo.
