title: Short-term moderate exercise programs reduce oxidative DNA damage as determined by high-performance liquid chromatography-electrospray ionization-mass spectrometry in patients with colorectal carcinoma following primary treatment.
abstract: OBJECTIVE
  Oxidative DNA damage is believed to be involved in tumor formation and may be an important biomarker for malignant transition or relapse. A decrease of such damage has been observed in human and animal studies following dietary intervention and/or changes in lifestyle such as physical exercise at different levels of intensity. The purpose of this study was to carry out a clinical trial comparing the effects of a short-term (2 weeks) exercise program of moderate intensity (0.3-0.4 x maximal exercise capacity) (MI) versus high intensity (0.5-0.6 x maximal exercise capacity) (HI) on individual urinary excretion of 8-oxo-dG before and after completion of the exercise programs.
  
  
  METHODS
  In this short-term, prospective and randomized trial, 19 patients with colorectal cancer were allocated to the MI group following primary therapy and 29 to the HI group. Urinary 8-oxo-dG excretion concentration was determined by a highly sensitive detection method using high-performance liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS). Concentrations were determined immediately before and after completion of the exercise programs.
  
  
  RESULTS
  Using HPLC-ESI-MS, it was shown that MI exercise significantly reduced urinary 8-oxo-dG excretion levels from 8.47 +/- 1.99 to 5.81 +/- 1.45 (ng/mg creatinine, mean +/- SE, p = 0.02), whereas HI exercise resulted in a non-significant increase from 5.00 +/- 1.31 to 7.11 +/- 1.63 (ng/mg creatinine, p = 0.18). Clinical characteristics (gender, age, body mass index (BMI), diet, chemotherapy/irradiation) were not associated/correlated with urinary 8-oxo-dG levels.
  
  
  CONCLUSIONS
  By using HPLC-ESI-MS it was shown that short-term MI exercise after primary therapy in patients with colorectal cancer was associated with lower levels of urinary 8-oxo-dG, suggesting decreased oxidative DNA damage. In contrast, HI exercise tended to increase DNA damage. A prospective trial is now warranted to prove that reduced oxidative DNA damage lowers the risk of relapse of colorectal cancer in treated patients.
authors.affiliation: Oncology Department, Reha-klinik Ob der Tauber, Academic Teaching Hospital, University of Heidelberg, Bad Mergentheim, Germany. allgayer@reha-klinik-odt.de
authors.forename: Hubert
authors.initials: H
authors.lastname: Allgayer
authors.forename: Robert W
authors.initials: RW
authors.lastname: Owen
authors.forename: Jagadeesan
authors.initials: J
authors.lastname: Nair
authors.forename: Bertold
authors.initials: B
authors.lastname: Spiegelhalder
authors.forename: Jürgen
authors.initials: J
authors.lastname: Streit
authors.forename: Christoph
authors.initials: C
authors.lastname: Reichel
authors.forename: Helmut
authors.initials: H
authors.lastname: Bartsch
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D014408:Biomarkers, Tumor / Q000652:urine; D002277:Carcinoma / Q000235:genetics / Q000628:therapy* / Q000652:urine; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D015179:Colorectal Neoplasms / Q000235:genetics / Q000628:therapy* / Q000652:urine; D003131:Combined Modality Therapy / Q000379:methods; D004249:DNA Damage / Q000235:genetics*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000235:genetics*; D011446:Prospective Studies; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine