Small dense LDL is more susceptible to glycation than more buoyant LDL in Type 2 diabetes

Clin Sci (Lond). 2013 Mar;124(5):343-9. doi: 10.1042/CS20120304.

Abstract

Glycation of apoB (apolipoprotein B) of LDL (low-density lipoprotein) increases its atherogenicity. Concentrations of both serum glyc-apoB (glycated apoB) and SD-LDL (small dense LDL) (syn LDL3; D=1.044-1.063 g/ml) are increased in diabetes and are closely correlated. We studied whether SD-LDL is more susceptible to glycation in vitro than more buoyant LDL in statin- and non-statin-treated Type 2 diabetes mellitus. Serum SD-LDL apoB and glyc-apoB on statins was 20±2 (means±S.D.) and 3.6±0.41 compared with 47±3 and 5.89±0.68 mg/dl in those not receiving statins (P<0.001 and <0.01, respectively). There was a dose-dependent increase in glycation on incubation of LDL subfractions with glucose, which was accompanied by an increase in LPO (lipid peroxide) and electrophoretic mobility and a decrease in free amino groups. SD-LDL was more susceptible to these changes than more buoyant LDL. Both SD-LDL and more buoyant LDL from statin-treated patients were less susceptible to glycation. There were fewer free amino groups on LDL subfractions from statin-treated patients, which may contribute to this resistance. In conclusion, greater susceptibility of SD-LDL to glycation is likely to contribute to the raised levels of circulating glyc-apoB in diabetes. Statins are associated with lower levels of both SD-LDL and glyc-apoB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apolipoproteins B / chemistry
  • Apolipoproteins B / metabolism*
  • Atherosclerosis / metabolism
  • Blood Glucose / metabolism
  • Coronary Disease / metabolism
  • Diabetes Mellitus, Type 2 / metabolism*
  • Electrophoretic Mobility Shift Assay
  • Female
  • Glycosylation
  • Humans
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors / therapeutic use
  • Hyperlipidemias / drug therapy
  • Hyperlipidemias / metabolism*
  • Lipoproteins, LDL / chemistry
  • Lipoproteins, LDL / metabolism*
  • Male
  • Middle Aged
  • Particle Size

Substances

  • Apolipoproteins B
  • Blood Glucose
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • Lipoproteins, LDL