Evaluation of hsa-let-7d-5p, hsa-let-7g-5p and hsa-miR-15b-5p plasma levels in patients with Alzheimer’s disease

Abstract

Background Alzheimer's disease (AD) is a progressive neurodegenerative disorder MicroRNAs (miRNAs) may be promising diagnostic biomarkers for AD. Previous evidence shows that miR-15b-5p, hsa-let7g-5p and hsa-let7d-5p might confer potential blood biomarkers for timely diagnosis of AD. Therefore, in this replication study, we aimed to investigate the serum transcript level of these miRNAs to assess for their potential as diagnostic or prognostic biomarker in AD patients. Methods Blood samples were obtained from 50 AD patients and 50 age-and sex-matched healthy individuals. Then, total RNA was extracted from serum samples, cDNA was synthesized, and the expression level of miRNAs was measured by the real-time PCR method. ResultsThe expression level of hsa-let7d-5p (fold change = 2.14, P = 0.007) and hsa-let7g-5p (fold change = 1.94; P = 0.013) was significantly increased in the AD patients compared to control individuals. However, the difference in the transcription of miR-15b-5p between the two groups was not statistically significant (fold change = 1.08; P = 0.76). The AROC for transcript levels of hsa-let-7d-5p was 0.68 (P = 0.014; 95% CI, 0.39-0.88) and it was 0.64 for hsa-let-7g-5p (P = 0.028; 95% CI, 0.27-0.89). The cut-off value for let-7d-5p had 0.82 sensitivity and 0.34 specificity. Moreover, the cut-off value for hsa-let-7g-5p indicated a 0.79 sensitivity and 0.28 specificity. ConclusionOur findings suggest the potential of measuring the transcript levels of hsa-let7d-5p and hsa-let7g-5p miRNAs as a diagnostic biomarker for AD.

Blood-Based Biomarkers for Alzheimer’s Disease Diagnosis and Progression: An Overview

“…Subsequent investigations have shown that upregulation of miR-590-5p and miR-142-5p, along with downregulation of miR-194-5p, is distinctive of AD subjects compared to healthy volunteers [ 212 ]. Moreover, enhanced plasma concentrations of hsa-let7d-5p and hsa-let7g-5p were detected in a study comprising 50 AD and 50 age- and gender-matched controls [ 213 ].…”

“…Table 2 relates the main findings on circulatory ncRNA dysregulation in AD [ 17 , 210 , 211 , 212 , 213 , 218 , 220 , 222 , 223 , 224 , 225 , 226 , 227 , 231 , 232 , 233 , 234 , 235 , 237 , 238 , 242 , 246 , 247 , 248 , 249 , 250 , 251 , 252 , 253 , 254 , 255 , 256 , 257 , 258 , 259 ].…”

A Comprehensive Review on Function of miR-15b-5p in Malignant and Non-Malignant Disorders

“…Although in vitro studies indicated possible role of miR-15b-5p in the pathogenesis of Alzheimer’s disease ( 36 ), serum levels of miR-15b-5p were not significantly different between patients with Alzheimer’s disease and healthy subjects ( 72 ).…”

MicroRNA Networks in Cognition and Dementia

“…Multiple reports have examined the regulation of let-7 members in neurodegenerative disease such as AD. Independent replicate studies discovered that expression of both let7g-5p and let7d-5p is significantly increased in blood samples from multiple AD cohorts [ 28 ]. Additionally, a study by Derkow et al, investigated whether brain-localized neurotoxic let-7 transcripts are released into the cerebrospinal fluid (CSF) and could serve as clinical biomarkers [ 23 ].…”