Non-invasive measurement of advanced glycation end products in patients with cerebral infarction

Background and purpose: Oxidative modification of carbohydrates and lipids enhances the formation of advanced glycation end products (AGEs). Although AGEs formation is markedly accelerated in hyperglycemia, its formation occurs in normoglycemia (e.g., during ischemic stroke) (1) and initiates a range of inflammatory responses (2). Recently, an AGE Reader (DIAGNOPTICS, USA) has become available to measure skin autofluorescence non-invasively. We used it to test our hypothesis that skin AGEs level increases in proportion to the progression of systemic atherosclerosis, even in patients with cerebral infarction, and is therefore available as a marker for predicting recurrence of ischemic stroke. In this study, we investigated the levels of skin AGEs in patients with chronic cerebral infarction, patients with silent infarction and age-matched controls. We also examined the effect of angiotension II receptor blocker (ARB) on the level of advanced glycation (3). Methods: We measured skin AGEs levels in patients with chronic symptomatic cerebral infarction (n=107) and asymptomatic cerebral infarction (n=26), as well as age-matched controls (n=25), using an AGE Reader. Patients with chronic symptomatic cerebral infarction were separated into two groups; those who received ARB and those who did not. Results: Skin AGEs levels in patients with symptomatic cerebral infarction were significantly increased compared with the control group (p<0.05; 2.1127±0.5355 v.s. 2.0202±0.4005). AGEs in patients with asymptomatic cerebral infarction were not increased versus the controls (p<0.05; 1.9781±0.3732 v.s. 2.0202±0.4005). However, AGEs in the symptomatic and asymptomatic groups were not significantly different. AGEs in the groups that did and did not receive ARB were also not significantly different. Conclusion: Our data suggest that increased formation of AGEs may be an indicator of oxidative stress, not only in diabetes and renal failure, but also in chronic cerebral infarction. Further study will be required to establish whether skin AGE level is a useful parameter for predicting recurrence of ischemic stroke.