title: Circadian time structure of circulating plasma lipid peroxides, antioxidant enzymes and other small molecules in peptic ulcers.
abstract: BACKGROUND
  The circadian rhythm, as part of a broad time structure (chronome) of lipid peroxides and antioxidant defense mechanisms may relate to prevention, efficacy and management of preventive and curative chronotherapy.
  
  
  METHODS
  Fifty newly diagnosed patients with peptic ulcers, 30-45 years of age, and 60 age-matched clinically healthy volunteers were synchronized for one week with diurnal activity from about 06:00 to about 22:00 and nocturnal rest. Breakfast was served around 08:30, lunch around 13:30 and dinner around 20:30. Drugs known to affect the free-radical systems were not taken. Blood samples were collected at 6-hour intervals for 24h under standardized, presumably 24-hour synchronized conditions. Plasma lipid peroxides, in the form of malondialdehyde (MDA), blood superoxide dismutase (SOD), glutathione peroxide (GPx), glutathione reductase (GR), catalase (CAT) activities, and serum total protein, albumin, ascorbic acid, total serum cholesterol, and HDL-cholesterol concentrations were determined.
  
  
  RESULTS
  By population-mean cosinor analysis, a marked circadian variation was demonstrated for all variables in healthy subjects and in ulcer patients (p<0.001). As compared to controls, patients had a lower MESOR of MDA, SOD, GPx, GR, ascorbic acid, and HDL-C. They also had smaller circadian amplitude of SOD, CAT, GPx, GR, ascorbic acid, T-C, and HDL-C, but larger circadian amplitude of MDA and albumin. As compared to healthy subjects, the circadian acrophase of ulcer patients occurred later for MDA and GR and earlier for GPx.
  
  
  CONCLUSIONS
  Mapping circadian rhythms, important chronome components that include trends with age and extra-circadian components characterizing antioxidants and pro-oxidants, is needed for exploring their putative role as markers in the treatment and management of peptic ulcers.
authors.affiliation: Department of Biochemistry, King George's Medical University, Lucknow, 226003 UP, India. Electronic address: ranjanasingh.2509@rediffmail.com.
authors.forename: Ranjana
authors.initials: R
authors.lastname: Singh
authors.affiliation: Department of Biochemistry, T S Misra Medical College and Hospital, Amausi, Lucknow, 226008 UP, India.
authors.forename: Rajesh Kumar
authors.initials: RK
authors.lastname: Singh
authors.affiliation: Department of Biochemistry, SGRR Institute of Medical & Health Sciences, Patel Nagar, Dehradun, 248001 UK, India.
authors.forename: Tariq
authors.initials: T
authors.lastname: Masood
authors.affiliation: Department of Medicine, King George's Medical University, Lucknow, 226003 UP, India.
authors.forename: Anil Kumar
authors.initials: AK
authors.lastname: Tripathi
authors.affiliation: Department of Biochemistry, King George's Medical University, Lucknow, 226003 UP, India.
authors.forename: Abbas Ali
authors.initials: AA
authors.lastname: Mahdi
authors.affiliation: Department of Biochemistry, SGRR Institute of Medical & Health Sciences, Patel Nagar, Dehradun, 248001 UK, India.
authors.forename: Raj Kumar
authors.initials: RK
authors.lastname: Singh
authors.affiliation: Halberg Chronobiology Center, University of Minnesota, MN 55455, USA.
authors.forename: Othild
authors.initials: O
authors.lastname: Schwartzkopff
authors.affiliation: Halberg Chronobiology Center, University of Minnesota, MN 55455, USA.
authors.forename: Germaine
authors.initials: G
authors.lastname: Cornelissen
mesh_terms: D000328:Adult; D000418:Albumins / Q000032:analysis; D000975:Antioxidants / Q000032:analysis*; D001205:Ascorbic Acid / Q000097:blood; D001798:Blood Proteins / Q000032:analysis; D002374:Catalase / Q000097:blood / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D002940:Circadian Rhythm; D005980:Glutathione Reductase / Q000097:blood / Q000378:metabolism; D006801:Humans; D008054:Lipid Peroxides / Q000097:blood*; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D010437:Peptic Ulcer / Q000097:blood* / Q000175:diagnosis / Q000201:enzymology*; D013482:Superoxide Dismutase / Q000097:blood / Q000378:metabolism; D055815:Young Adult
chemical_list: D000418:Albumins; D000975:Antioxidants; D001798:Blood Proteins; D008054:Lipid Peroxides; D008315:Malondialdehyde; D002784:Cholesterol; D002374:Catalase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D001205:Ascorbic Acid
keywords: Antioxidant defense mechanisms; Chronome; Chronoprevention; Circadian; Gastric and/or duodenal mucosal erosion and ulceration; Lipid peroxides; Marker rhythm