Background: Recent studies showed that type 2 diabetes mellitus (T2DM) may increase the risk of cognitive impairment, but there are few biomarkers to diagnostically discriminate T2DM-associated cognitive impairment and cognitive impairment alone. In this study, we assessed certain cytokines involved in inflammation and vascular diseases and identified special panel of cytokines that could differentiate between T2DM and cognitive impairment.
Objective: To investigate associations and differences between T2DM and cognitive impairment by cytokines analysis.
Methods: A total of 264 participants were recruited, their blood samples were collected, and plasma and serum were separated and stored at - 80°C until the assessment of amyloid-β (Aβ)42, Aβ40 and 8 kinds of cytokines by Luminex multiplex assays.
Results: Plasma Aβ40 is higher whereas Aβ42/40 ratio is lower in cognitive impairment and T2DM-associated cognitive impairment compared to other groups. As compared to health control, YKL-40 level was upregulated in cognitive impairment, PRGN was downregulated in T2DM associated cognitive impairment, OPN was substantially decreased in T2DM, and IL-6 was elevated in cognitive impairment and T2DM-associated cognitive impairment. Interestingly, VEGF and S100B were induced in T2DM when compared with cognitive impairment, and NSE level in T2DM-associated cognitive impairment is significantly lower than in T2DM or cognitive impairment.
Conclusion: Aβ42, Aβ40, and Aβ42/40 ratio cannot distinguish T2DM-associated cognitive impairment from cognitive impairment. Certain cytokines (YKL-40, NSE, and VEGF) have good performance in distinguishing T2DM-associated cognitive impairment from simple cognitive impairment. Taken together, this may improve the accuracy of the diagnosis and establishment of individualized therapy.
Keywords: Biomarkers; cognitive impairment; serum cytokines; type 2 diabetes mellitus.