title: Impaired antioxidant action of high density lipoprotein in patients with type 1 diabetes with normoalbuminuria and microalbuminuria.
abstract: OBJECTIVE
  Patients with type 1 diabetes, in the absence of chronic complications, have serum concentrations of high density lipoprotein cholesterol (HDL-C) similar to the general population. However, their HDL particles may be dysfunctional. We aimed to evaluate the antioxidant effect of HDL2 and HDL3 obtained from Caucasian males with type 1 diabetes with normoalbuminuria and microalbuminuria.
  
  
  METHODS
  Twenty Caucasian men with type 1 diabetes (10 with normoalbuminuria and 10 with microalbuminuria) and 10 healthy Caucasian men participated in the study. Lipoproteins were obtained by density gradient ultracentrifugation. The antioxidant effect of HDL was assessed by measuring lipid hydroperoxide (LOOH) concentration after 3h of pooled LDL oxidation catalyzed by 5μM CuSO4 in the absence or presence of HDL2 or HDL3.
  
  
  RESULTS
  The control, normoalbuminuria, and microalbuminuria groups had similar HDL-C concentration and estimated glomerular filtration rate. Glycemic control was similar between diabetes groups (HbA1c 8.1±0.9% and 8.3±0.7%, P=0.70), but estimated glucose disposal rate was lower in patients with microalbuminuria (8.0±0.6 and 4.5±1.1mg/kg/min, P<0.01). The relative antioxidant effect of HDL2 from control, normoalbuminuria, and microalbuminuria groups were 92.8±2.4%, 85.4±1.7%, and 74.2±4.6%, respectively (P<0.01), and the HDL3 effect were 95.0±2.2%, 86.4±4.4%, and 75.3±4.2%, respectively (P<0.01).
  
  
  CONCLUSIONS
  Both HDL2 and HDL3 inhibited LOOH formation in copper-catalyzed oxidation of LDL in vitro. Overall, this antioxidant effect was lower in Caucasian men with type 1 diabetes, and was further compounded in those with microalbuminuria.
authors: Postgraduate Program in Health Sciences, Universidade Estadual de Londrina, Londrina, PR, Brazil.
authors: Emerson
authors: E
authors: Sampaio
authors: Décio Sabbatini
authors: DS
authors: Barbosa
authors: Tânia Longo
authors: TL
authors: Mazzuco
authors: Valéria Sutti
authors: VS
authors: Nunes
authors: Marisa
authors: M
authors: Passarelli
authors: Edna Regina
authors: ER
authors: Nakandakare
authors: Alexandre José Faria
authors: AJ
authors: Carrilho
mesh_terms: D000328:Adult; D000419:Albuminuria / Q000378:metabolism*; D000975:Antioxidants / Q000502:physiology*; D008076:Cholesterol, HDL / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000503:physiopathology; D006801:Humans; D008054:Lipid Peroxides / Q000096:biosynthesis / Q000097:blood; D008075:Lipoproteins, HDL / Q000097:blood / Q000378:metabolism*; D053439:Lipoproteins, HDL2 / Q000502:physiology; D053440:Lipoproteins, HDL3 / Q000502:physiology; D008077:Lipoproteins, LDL / Q000378:metabolism; D008297:Male
chemical_list: D000975:Antioxidants; D008076:Cholesterol, HDL; D008054:Lipid Peroxides; D008075:Lipoproteins, HDL; D053439:Lipoproteins, HDL2; D053440:Lipoproteins, HDL3; D008077:Lipoproteins, LDL