title: The relation between serum MDA and cystatin C levels in chronic spinal cord injury patients.
abstract: OBJECTIVE
  The assessment of renal function is particularly important in patients with spinal cord injury (SCI). Creatinine (Cr) is known to be unsuitable as a marker of renal function in SCI because of muscle wasting. Although cystatin C (cys-C) is more reliable than Cr, its expression may be affected by oxidative stress accompanying SCI. The aim of the study was to estimate the cys-C levels in SCI patients with normal functioning kidneys. The prooxidant/antioxidant state in plasma of the patients and controls was measured, and any correlations between these parameters and cys-C were determined.
  
  
  METHODS
  Blood samples from 41 chronic SCI patients and 13 controls were obtained. Serum Cr was assayed by the Cobas Integra 400 autoanalyzer and cys-C by particle-enhanced immunoturbidimetry. Heparinized plasma was used for biochemical determinations of vitamin E, total antioxidant status (TAS) and malondialdehyde (MDA).
  
  
  RESULTS
  Cr, TAS and MDA levels were significantly lower in SCI patients compared to the controls (P = 0.007, P = 0.019, P = 0.000, respectively), whereas no difference was seen in cys-C and vit E concentrations. Body mass indices (BMI) of SCI patients were less than those of the controls (P = 0.03). No correlation existed between cys-C and MDA in SCI patients and controls. Cys-C levels were independent from the body mass indices of subjects.
  
  
  CONCLUSIONS
  In our study, although BMI and MDA were both affected in SCI patients, cys-C levels were unchanged. Therefore, the measurement of cys-C appeared to be of value for the follow-up of renal function in SCI. The low MDA levels observed in these patients suggest that various adaptation mechanisms may be relevant for subjects undergoing prolonged stress situations.
authors.affiliation: Department of Biochemistry, Istanbul Faculty of Medicine, Istanbul University, Capa 34093, Istanbul, Turkey. kocakhikmet@hotmail.com
authors.forename: Hikmet
authors.initials: H
authors.lastname: Koçak
authors.forename: Yildiz
authors.initials: Y
authors.lastname: Oner-Iyidoğan
authors.forename: Figen
authors.initials: F
authors.lastname: Gürdöl
authors.forename: Taner
authors.initials: T
authors.lastname: Koçak
authors.forename: Deniz
authors.initials: D
authors.lastname: Esin
mesh_terms: D000293:Adolescent; D000328:Adult; D000975:Antioxidants / Q000032:analysis; D015992:Body Mass Index; D055316:Cystatin C; D015891:Cystatins / Q000097:blood*; D005919:Glomerular Filtration Rate; D006801:Humans; D007674:Kidney Diseases / Q000209:etiology; D008315:Malondialdehyde / Q000097:blood*; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology; D013119:Spinal Cord Injuries / Q000097:blood* / Q000150:complications; D014810:Vitamin E / Q000097:blood
chemical_list: D000975:Antioxidants; C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D014810:Vitamin E; D008315:Malondialdehyde