Oxidative stress markers in cognitively intact patients with diabetic neuropathy.

Various forms of vascular injury are frequently associated with type-2 diabetes mellitus (DM2). Macro-angiopathy has alarming signs and symptoms such as those seen with stroke or heart attack, however the presentation of small vessel disease is generally more subtle and therefore usually unnoticed for a long period of time. While it may affect any organ, complications involving the nervous system such as diabetic poly-neuropathy (DPN) are especially debilitating, and it may also be a risk factor for other brain disorders such as dementia. The underlying mechanisms are likely to be multi-faceted, but piling evidence indicates oxidative stress as one of the crucial factors. Here we evaluate the oxidative profile of patients with DM2. The total anti-oxidant capacity appears to be reduced in DM2 with or without complications. Of the specific bio-markers studied, the levels of tissue-damage indicator malon-dialdehyde (MDA) were significantly lower in the DM2 + DPN population only. These results suggest that diabetic patients present with wavering oxidative status, and the low MDA concentrations in patients with complications such as DPN may represent either an exhausted anti-oxidative defense system or a response to anti-inflammatory medications. The findings may also support the use of anti-oxidants such as vitamins A and E.