Association of cerebrospinal fluid Neurogranin with Alzheimer’s disease

Cerebrospinal fluid (CSF) Neurogranin has recently been proposed as a potential biomarker for cognitive decline and brain injury in Alzheimer's disease (AD). To test whether CSF Neurogranin levels are increased in AD and its association with cognitive decline, we examined 99 cognitively normal (CN) subjects, 171 patients with mild cognitive impairment (MCI), and 81 patients with AD in the cross-sectional study from the Alzheimer's Disease Neuroimaging Initiative (ADNI). The results showed that CSF Neurogranin was increased in both AD and MCI compared with controls. CSF Neurogranin was particularly high in patients with MCI and AD dementia with Aβ pathologic features. Neurogranin levels were significantly higher in females compared to males with MCI. Levels of Neurogranin between the males and females with AD and CN did not differ. Neurogranin levels were significantly higher in APOE e4 carriers compared to APOE e4 non-carriers with MCI. Levels of Neurogranin between the APOE e4 carriers and APOE e4 non-carriers with AD and CN did not differ. Elevated CSF Neurogranin levels were positively correlated with levels of total tau and P-tau in AD. The results indicated that CSF Neurogranin was increased at the prodromal stage of AD and might reflect synaptic injury as cognitive decline in AD.