title: Lipid peroxidation and total antioxidant capacity in vitreous, aqueous humor, and blood samples from patients with diabetic retinopathy.
abstract: OBJECTIVE
  To evaluate levels of malondialdehyde and the total antioxidant capacity (TAC) in the blood, aqueous humor, and vitreous bodies of diabetic and nondiabetic patients. We also measured the blood energy charge potential (ECP).
  
  
  METHODS
  We examined 19 patients with type 2 diabetes mellitus and diabetic retinopathy. Ten were scheduled for cataract surgery and pars plana vitrectomy because of proliferative diabetic retinopathy (PDR). The other nine, with mild nonproliferative PDR (NPDR), and fourteen nondiabetic, age-matched subjects enrolled as a control group were scheduled for cataract surgery and vitrectomy because of epiretinal membranes. Blood, aqueous humor and vitreous body samples were collected at the time of surgery. Malondialdehyde concentrations and blood ECP were measured with high-performance liquid chromatography. The TAC of the samples was estimated with the oxygen radical absorbance capacity method.
  
  
  RESULTS
  The level of blood and vitreous malondialdehyde in the PDR group was significantly higher compared to controls and to NPDR patients. PDR patients also had lower levels of TAC at the vitreous body and aqueous humor level, but not at the blood level, compared to controls and with NPDR patients. In all diabetic patients, the blood ECP values were significantly lower, compared to control subjects.
  
  
  CONCLUSIONS
  Our data support the hypothesis that oxidative stress and the decrease of antioxidant defenses are associated with the progression of diabetic retinopathy to its proliferative form. Antioxidant supply may have the effect of correcting oxidative stress and inhibiting disease progression.
authors.affiliation: Ophthalmology Unit, Department of Biopathology, Tor Vergata University of Rome, Rome, Italy. eyes2005@libero.it
authors.forename: Raffaele
authors.initials: R
authors.lastname: Mancino
authors.forename: Donato
authors.initials: D
authors.lastname: Di Pierro
authors.forename: Chiara
authors.initials: C
authors.lastname: Varesi
authors.forename: Angelica
authors.initials: A
authors.lastname: Cerulli
authors.forename: Alessandra
authors.initials: A
authors.lastname: Feraco
authors.forename: Claudio
authors.initials: C
authors.lastname: Cedrone
authors.forename: Maria Dolores
authors.initials: MD
authors.lastname: Pinazo-Duran
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Coletta
authors.forename: Carlo
authors.initials: C
authors.lastname: Nucci
mesh_terms: D000368:Aged; D000975:Antioxidants / Q000032:analysis*; D001082:Aqueous Humor / Q000737:chemistry*; D001774:Blood Chemical Analysis; D002851:Chromatography, High Pressure Liquid; D003924:Diabetes Mellitus, Type 2; D003930:Diabetic Retinopathy / Q000378:metabolism* / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008315:Malondialdehyde / Q000032:analysis; D018384:Oxidative Stress; D014822:Vitreous Body / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D008315:Malondialdehyde