Evaluation of hsa-let-7d-p, hsa-let-7g-5p and hsa-miR-15b-5p level in plasma of patients with Alzheimer’s disease compared to healthy controls

Abstract

Alzheimer disease is a progressive neurodegenerative disorder characterized by memory impairment, personality disorder, and social dysfunction, but an intact level of consciousness. Memory impairment is the most obvious manifestation of the disease, which is limited to the recent events in the early stages, but ultimately proceeds to the involvement of the long-term memory. Currently, there is no known drug or other intervention with definite preventive effects on the onset or progression of Alzheimer’s disease in the elderly. Due to the natural history of the disease and its adverse effects on the individuals’ mental health, timely diagnosis of Alzheimer’s disease is of great importance. However, the lack of a definite biomarker for Alzheimer’s disease is one of the main problems with the early detection of the disease. In recent years, efforts to find biomarkers for the early diagnosis of Alzheimer’s disease have drawn the researchers’ attention to a group of biomolecules, named microRNAs, which may act as promising diagnostic biomarkers of the Alzheimer’s disease. Recent studies have led miRNAs like miRNA15b5p, hsalet7g5p, and has-let7d5p to be considered as blood biomarkers of Alzheimer s disease. . Therefore, in the present project, our aim is to investigate the plasma expression of these genes in patients with Alzheimer's disease and its comparison with normal individuals. Materials and methods: During the diagnosis process of Alzheimer's patients, a collection of 50 blood samples from affected patients and 50 healthy individuals collected by matched to the patient group. Then Total RNA of each sample was extracted, and the expression level of target genes have been measured by Real time PCR method and evaluated by suitable Statistical tests and P value <0.05 was considered as significant. Results: The relative expression of two of the three genes studied in the patient's samples increased significantly compared to the healthy samples (P value let7d5p = 0.007) and ( P value let7g5p = 0.013) However, the differences in the third gene between the two groups were statistically insignificant (p value miR-15b . = 0.7624).