Enhanced susceptibility of low-density lipoprotein to oxidation in wet type age-related macular degeneration in male patients

Abstract

Objective: To determine the susceptibility of low-density lipoprotein (LDL) to oxidation in the plasma of male patients with wet type age related macular degeneration (AMD) and in a similar control group, in order to evaluate the LDL oxidative status as risk factor of AMD.

Methods: We conducted this study in the Retina Service, Department of Ophthalmology, Nikookari Eye Hospital-Drug of Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran during the period between October 2004 and December 2005. Sixty male patients with AMD (mean age 67 +/- 16 years) with BMI 4.1 +/- 1.3 were selected as the patient group. The control group consisted of 60 males, apparently healthy, and without ophthalmologic signs and family history of AMD. Low-density lipoprotein was isolated by gradient ultracentrifugation and susceptibility of LDL to in vitro copper-mediated oxidation was assayed by measuring conjugated dienes production (lag phase duration) at 234 nm. Lipid and lipoproteins were determined by standard methods.

Results: Comparing with control, significant reduction in the duration of lag phase (p<0.004) and a significant increase in LDL-C concentrations (p=0.006), were noticed. No significant change in cholesterol (p>0.3), triglyceride (p>0.1) and high density lipoprotein cholesterol (p>0.1) levels were found between control and patient groups. A significant negative correlation between Lag phase and LDL-C levels (p=0.004, r=-0.364) was found in the patient group.

Conclusion: The increased LDL concentration and enhanced susceptibility of LDL to oxidation may play a roll in the wet type AMD process.