Abstract
Abstract: :
Purpose: : Age-related vitreous liquefaction is considered to be possibly due to crossline of collagen fibers and depolymerization of hyaluronic acid (HA). It is known that posterior vitreous detachment occurs at earlier ages in patients with diabetes mellitus (DM). The concentrations of advanced glycation end products (AGEs) in serum and vitreous are increased in patients with DM. In addition, AGEs are reported to show photosensitizer activities. Therefore, we tested the effect of AGEs on photo-induced vitreous liquefaction of HA. Methods: In the preparatory experiment, the retention time of Pullulan as a molecular weight marker was measured, using high-performance liquid chromatography. In the main experiment, 0.02% HA solutions were used, half of which contained AGEs and half of which did not. These solutions were then either irradiated using a Xe lamp of 300W white light, or kept in the dark for 2, 3 or 4 hours. The measured retention times suggested the change in molecular weight of HA. Results: In the preparatory experiment, the retention time and logarithm of molecular weight were negatively correlated (r= -0.995). In the main experiment, the results were as following; 1) The retention time was delayed by irradiation time-dependently, in both samples containing AGEs and not containing AGEs. 2) In the irradiated group, adding AGEs significantly delayed the retention time. 3) In the non-irradiated group, there is no difference in the retention time of samples containing AGEs and not containing AGEs. Conclusions: Irradiation decreases the molecular weight of HA; adding AGEs promotes this change. The photosensitizer activity of AGEs may be associated with earlier vitreous liquefaction in patients with DM.
Keywords: diabetes • vitreous