Enhanced susceptibility of low-density lipoprotein to oxidation in wet type age-related macular degeneration in male patients
چکیده
Objectives: 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. Conclusions: The increased LDL concentration and enhanced susceptibility of LDL to oxidation may play a roll in the wet type AMD process.