The neuronal pentraxin receptor (NPTXR) as a candidate biomarker of synaptic dysfunction in mild cognitive impairment

Abstract Background Early deficits of cognitive symptoms have molecular background closely related to Alzheimer’s Disease (AD). Before developing full‐blown AD, mild cognitive impairment (MCI) develops. It has been suggested that synaptic pathology is closely associated with memory impairment in the early phase of the disease and may be monitored by assessment of the synaptic proteins in cerebrospinal fluid (CSF), like neuronal pentraxin receptor (NPTXR). The highest expression of NPTXR and involvement in neuronal processes have been observed in the hippocampus and cortex. This candidate biomarker of synaptic dysfunction may have a crucial role in synaptic transmission and modulation of memory processes with other synaptic proteins. The purpose of the our investigation was to assessed the neuronal pentraxin receptor (NPTXR) level in cerebrospinal fluid (CSF) in MCI patients. Method The study included 17 patients with MCI and 17 non‐demented controls. The CSF levels of NPTXR and classical AD biomarkers, such as Aβ‐42, Aβ‐42/Aβ‐40, Tau, and pTau181, were assessed by commercially available immunoenzyme assays. Result The CSF concentration of NPTXR was significantly lower in MCI patients compared to non‐demented controls. Moreover, NPTXR level was positively correlated with Tau181, Aβ‐42, and total Tau proteins in MCI patients. Conclusion Our results suggest that Neuronal Pentraxin Receptor may be one of the biomarker reflecting synaptic dysfunction in MCI patients. These preliminary results seem very promising, particularly for the early diagnosis of Alzheimer’s disease. Future research concerning NPTXR is necessary to understand better the role of the protein in early pathological processes of the disease.