title: Effects of Tibetan turnip (Brassica rapa L.) on promoting hypoxia-tolerance in healthy humans.
abstract: BACKGROUND
  Tibetan turnip (Brassica rapa L.), widely distributed in Tibet region, is an edible and medical plant with effects of "tonic and anti-hypoxia" "heat-clearing and detoxification" and "alleviating fatigue" according to traditional Tibetan medical books.
  
  
  OBJECTIVE
  This research systematically studied the effects of Tibetan turnip on promoting hypoxia-tolerance in humans and the mechanisms.
  
  
  METHODS
  A 7-d, self-control and single-blind human feeding trial was conducted among 27 healthy subjects with 8 males and 10 females in feeding group fed with 7.5g turnip powder 2 times daily while 4 males and 5 females in control group fed with 7.5g radish powder twice a day. Subjects were required to undergo a hypoxia tolerance test (7.1% O2) and a cardiopulmonary function evaluation (Bruce treadmill protocol) before (1st day) and after (9th day) the trial. Simultaneously, the anti-oxidative activities (SOD, CAT, GSH-Px, MDA), routine and biochemical analyses of blood samples were evaluated.
  
  
  RESULTS
  The females' SpO2increased significantly by 6.4% at the end of the hypoxia tolerance test after taking turnips (p<0.05), and the hypoxia symptoms in most of the subjects were alleviated as well. The anaerobic threshold, peak O2pulse and peak VO2/kg were significantly improved after 7-d turnip consumption during the Bruce treadmill test (p<0.05). As for the blood analysis, anti-oxidative activities were boosted effectively after the 7-d treatments. Moreover, mean corpuscular hemoglobin concentration (MCHC) in the males of feeding group increased significantly (p<0.05). However, little changes of all variables were observed in the control group.
  
  
  CONCLUSIONS
  Consumption of Tibetan turnips for 7 days likely contributed to the hypoxia tolerance in healthy humans, which could be due to its abilities of improving oxygen uptake and delivery, enhancing body antioxidant capacity and increasing MCHC. However, further studies with larger samples and double-blind design are warranted, and future studies covering more diverse populations (unhealthy, athletic) would be also considered. Moreover, researches on identifying Tibetan turnip's active compounds are desired as well.
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China.
authors.forename: Bingquan
authors.initials: B
authors.lastname: Chu
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China.
authors.forename: Chun
authors.initials: C
authors.lastname: Chen
authors.affiliation: Aviation Medicine Training Center of Hangzhou, Hangzhou 310013, Zhejiang, China.
authors.forename: Jiaojie
authors.initials: J
authors.lastname: Li
authors.affiliation: Aviation Medicine Training Center of Hangzhou, Hangzhou 310013, Zhejiang, China.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China.
authors.forename: Yunhong
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China.
authors.forename: Weimin
authors.initials: W
authors.lastname: Tang
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Jin
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China. Electronic address: yzhang@zju.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000064:Acclimatization; D000328:Adult; D000531:Altitude; D000532:Altitude Sickness / Q000097:blood / Q000503:physiopathology / Q000517:prevention & control*; D015308:Anaerobic Threshold; D000975:Antioxidants / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D029741:Brassica rapa / Q000737:chemistry*; D000072599:Cardiorespiratory Fitness; D002681:China; D004909:Erythrocyte Indices; D005080:Exercise Test; D005260:Female; D006304:Health Status; D064368:Healthy Volunteers; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D010101:Oxygen Consumption; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage* / Q000302:isolation & purification; D010946:Plants, Medicinal; D016037:Single-Blind Method; D013997:Time Factors; D055815:Young Adult
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D006454:Hemoglobins; D010936:Plant Extracts
keywords: Anti-hypoxia capacity; Cardiopulmonary function; Human feeding trial; Hypoxia tolerance; Tibetan turnip (Brassica rapa L.)