title: The effect of RHIZOMA COPTIDIS and COPTIS CHINENSIS aqueous extract on radiation-induced skin injury in a rat model.
abstract: BACKGROUND
  Radiation-induced skin injury is a common complication of radiotherapy. The RHIZOMA COPTIDIS and COPTIS CHINENSIS aqueous extract (RCE) can ameliorate radiation-induced skin injury in our clinical observation. But, the protective mechanism of RHIZOMA COPTIDIS and COPTIS CHINENSIS in radiation-induced skin injury remains unclear.
  
  
  METHODS
  In this experiment, we developed a radiation-induced skin injury rat model to study the mechanism. The animals were randomly divided into control group, treatment group, radiation group, and treatment and radiation group. 5 rats in each group were separately executed on 2 d and 49 d post-radiation. The semi-quantitative skin injury score was used to measure skin reactions by unblinded observers, and hematoxylin and eosin staining was used to evaluate the damage areas by irradiation. The MDA content, SOD activity of skin and serum were measured to detect the oxidative stress.
  
  
  RESULTS
  Acute skin reactions were caused by a single dose of 45 Gy of β-ray irradiation, and the skin injury could be found in all rats receiving irradiation based on the observation of HE staining of skin at different time-points, while RCE could significantly ameliorate those changes. The MDA content in serum and skin of control rats was 4.13±0.12 mmol/ml and 4.95±0.35 mmol/mgprot on 2 d post-radiation. The rats receiving radiation showed an increased content of MDA (5.54±0.21 mmol/ml and 7.10±0.32 mmol/mgprot), while it was 4.57±0.21 mmol/ml and 5.95±0.24 mmol/mgprot after treated with RCE (p<0.05). Similar changes of the MDA content could be seen on 49 d post-radiation. However, the SOD activity of rats receiving radiation decreased compared with control group on both time-points, which was inhibited by RCE (p<0.05). Meanwhile, no valuable changes could be found between control group and treatment group on 2 d and 49 d.
  
  
  CONCLUSIONS
  Our study provides evidences for the radioprotective role of RCE against radiation-induced skin damage in rats by modulating oxidative stress in skin, which may be a useful therapy for radiation-induced skin injury.
authors.affiliation: Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, China.
authors.forename: Xi-Jing
authors.initials: XJ
authors.lastname: Wang
authors.forename: Shuai
authors.initials: S
authors.lastname: Lin
authors.forename: Hua-Feng
authors.initials: HF
authors.lastname: Kang
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Dai
authors.forename: Ming-Hua
authors.initials: MH
authors.lastname: Bai
authors.forename: Xiu-Long
authors.initials: XL
authors.lastname: Ma
authors.forename: Xiao-Bin
authors.initials: XB
authors.lastname: Ma
authors.forename: Meng-jie
authors.initials: MJ
authors.lastname: Liu
authors.forename: Xiao-Xu
authors.initials: XX
authors.lastname: Liu
authors.forename: Bao-Feng
authors.initials: BF
authors.lastname: Wang
mesh_terms: D000818:Animals; D039323:Coptis / Q000737:chemistry*; D000089042:Coptis chinensis; D004195:Disease Models, Animal; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D011832:Radiation Injuries / Q000188:drug therapy* / Q000201:enzymology / Q000378:metabolism / Q000517:prevention & control; D051381:Rats; D027343:Rhizome / Q000737:chemistry*; D012867:Skin / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism / Q000528:radiation effects; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D004365:Drugs, Chinese Herbal; D008315:Malondialdehyde; C107393:Coptidis rhizoma extract; D013482:Superoxide Dismutase