Evaluation of oxidative stress biomarkers in mild cognitive impairment and Alzheimer's disease: targeting dynamic thiol-disulfide homeostasis and ischemia-modified albumin.

Objectives: Oxidative stress plays a key role in the progression of chronic disorders including Alzheimer's disease (AD) and mild cognitive impairment (MCI). This study aimed to assess oxidative stress in MCI and AD patients using ischemia-modified albumin (IMA) and dynamic thiol - disulfide homeostasis (TDH), and to investigate their potential as prognostic biomarkers.

Methods: A total of 128 participants were included in this study: 44 with normal cognition, 44 with MCI, and 40 with AD. All patients were evaluated based on mental status, comorbidities, and laboratory parameters. Serum levels of native thiol, total thiol, disulfide bonds, and IMA were measured.

Result: Native and total thiol levels were significantly lower in late-stage AD patients compared to controls (p ≤ 0.05). Furthermore, thiol levels were also significantly lower in the combined middle- and late-stage AD group compared to controls (p ≤ 0.05). Although thiol levels in MCI patients were lower than in controls and higher than in AD, the differences were not statistically significant. Thiol levels positively correlated with MMSE scores (p ≤ 0.05) and showed a marked decline with advancing age (p < 0.001). Hypertensive patients also had significantly lower thiol levels compared to those without hypertension (p < 0.05).

Conclusion: Our findings suggest that total and native thiol levels decline with cognitive deterioration and advancing age. These oxidative stress biomarkers might hold potential as supportive tools in the prognostic assessment of patients, particularly those with Alzheimer's disease.