TXN and Alzheimer disease: When serum Trx80 levels were analyzed between these 4 groups (Fig. 1B), we observed that the SCI group had significantly lower Trx80 levels (3.56 ± 4.87 ng/ml) than the FINGER sub-study (19.46 ± 38.37 ng/ml; p < 0.01), MCI group (28.13 ± 30.39 ng/ml; p < 0.001), and AD group (25.50 ± 28.58 ng/ml; p < 0.001).