Comparison between the Plasma Levels of Long Noncoding RNA BDNF-AS in Patients with Alzheimer\'s disease and Healthy Subjects

BACKGROUND AND OBJECTIVE: Diagnosis of Alzheimer's disease usually occurs when serious damages have occurred in the brain and common treatments are ineffective in preventing it. One of the RNAs involved in Alzheimer's disease is a long noncoding RNA, called BDNF antisense (BDNF-AS). The aim of this study is to determine the presence and compare the BDNF-AS levels in plasma of Alzheimer's patients and healthy subjects, and to evaluate its potential as a plasma marker for Alzheimer's disease. METHODS: In this case-control study, 30 patients with late-stage Alzheimer's disease and 30 healthy subjects without neurological disease who matched the patients in terms of age were selected by a specialist according to the criteria for clinical diagnosis of Alzheimer's disease and their intravenous blood samples were collected. The plasma of the blood samples was isolated and total plasma RNA was extracted. After cDNA synthesis, the presence of BDNF-AS in plasma was examined by PCR. Finally, the relative level of BDNF-AS transcripts in plasma samples of patients with Alzheimer's disease and healthy subjects was evaluated using Real Time PCR. FINDINGS: The results of this study showed that long noncoding RNA BDNF-AS was present in the plasma of patients and controls. Comparison of Real Time PCR data showed that BDNF-AS levels in the plasma of patients (0.107±0.021) showed significant increase compared to healthy subjects (0.039 ± 0.006). CONCLUSION: The results of this preliminary study indicate that the levels of long noncoding RNA BDNF-AS in plasma can be used as a blood/plasma marker for the diagnosis of Alzheimer's disease