Abstract
Aim
To evaluate the relationship between Alzheimer’s disease (AD) with serum tau, neurofilament light polypeptide (NFL), neurogranin, chitinase-3-like protein 1 (YKL-40) and fatty acid binding protein-3 (FABP-3) as non-invasive markers for early diagnosis of AD.
Methods
Total 86 AD patients and 30 healthy individuals were recruited. Mini-Mental State Examination (MMSE), Clinical Dementia Rating Scale-Sum of Boxes (CDR-SB) scores, glucose and lipid profile parameters were assessed.
Results
AD patients were divided into three groups according to CDR: 33 mild, 29 moderate, and 24 severe stages. Serum total tau and NFL levels were higher, neurogranin, YKL-40, FABP-3 not changed in AD patients. Late onset AD was related with higher FABP-3 levels when compared to early onset. Glucose, total cholesterol, LDL were elevated in AD patients. We evaluated for the first time the combined effects of serum total tau-NFL as biomarkers in early diagnosis of AD, and assessed whether the created ROC curves had a strengthening effect on the parameters. Serum total tau values alone had the highest sensitivity and specificity. When NFL-total tau were combined, NFL sensitivity and specificity was higher compared to the values obtained alone. In addition, NFL was correlated to total tau. Both NFL and total tau were in close relationship with lipid profile parameters.
Conclusion
Our findings suggest that serum total tau alone is sufficient for the early diagnosis of AD; however, combinations of total tau-NFL biomarkers could also be used as screening tests. High glucose, total cholesterol, LDL support the relationship between AD and metabolic syndrome.