Identification of miR-708-5p in peripheral blood monocytes: Potential marker for postmenopausal osteoporosis in Mexican-Mestizo population

Abstract

Osteoporosis is the most frequent disorder of bone metabolism, owing to an alteration between osteoclast and osteoblast activity, which results from the interaction of genetic, environmental, and epigenetic factors. microRNAs, small non-coding RNAs of around 22 nucleotides with important regulatory roles in gene regulation, that target mRNAs for post-transcriptional destabilization have been suggested as biomarkers in several disorders. In this work, we used small RNA sequencing to identify microRNAs from peripheral blood monocytes that were differentially expressed between non-osteoporotic and osteoporotic Mexican postmenopausal women, to elucidate the potential role of microRNAs as non-invasive marker candidates in osteoporosis. We identified six candidate microRNAs: four were up-regulated (miR-708-5p, miR-34b-5p, miR-3161, miR-328-5p), while two were down-regulated (miR-4422 and miR-939-3p) in osteoporotic women. Differential expression was validated by quantitative RT-PCR and only the upregulation of miR-708-5p was found to be statistically significant. Bioinformatic analysis of target genes for miR-708-5p showed 15 signaling pathways related to bone metabolism. Since monocytes are osteoclast precursors, 10 potential target genes present in these pathways and related to osteoclastogenesis were identified ( AKT1, AKT2, CCND1, PARP1, SMAD3, CXCL5, FKBP5, MAP2K3, MMP2, and IKBKG). Five of them were found to be down-regulated according to microarray expression data. This is the first time that miR-708-5p has been identified in peripheral blood monocytes and associated with postmenopausal osteoporosis. Our results suggest that miR-708-5p reduces the expression of AKT1, AKT2, PARP1 FKBP5, and MP2K3 in peripheral blood monocytes contributing to an osteoporotic phenotype and could be a candidate marker for postmenopausal osteoporosis in Mexican population. Impact statement This is the first study in which hsa-miR-708-5p has been identified in peripheral blood monocytes (osteoclast precursors) and associated with postmenopausal osteoporosis through small RNA-Sequencing, in an Admixed Mexican Mestizo population. By conducting in silico and bioinformatic analyzes, we identified target genes and important signaling pathways involved in bone metabolism pointing hsa-miR-708-5p as a candidate marker for osteoporosis in Mexican population. These approaches provide a landscape of the post-transcriptional regulation, which can be useful for the management of postmenopausal osteoporosis along with the potential use of microRNAs as markers for its early detection.

Synergistic effects of miR-708-5p and miR-708-3p accelerate the progression of osteoporosis

“…Rafael et al. 23 previously detected the up-regulation of miR-708-5p in peripheral blood mononuclear cells of Mexican osteoporotic women, but we did not observe this in the osteoclast induction of BMMs. Therefore, future work should use PBMCs as the precursor to induce osteoclasts to detect changes in miR-708-5p expression because miRNAs in precursor cells from different sources may have different trends.…”

“…Dozens of miRNAs are considered to play a role in osteoporosis, 22 but the regulatory role of miR-708-5p and miR-708-3p in osteoporosis has rarely been reported. De-La-Cruz-Montoya et al 23 showed for the first time that miR-708-5p was up-regulated in peripheral blood mononuclear cells of Mexican women with osteoporosis, and could be used as a marker for osteoporosis. Of note, miR-708-5p and miR-708-3p are processed from the same pre-miRNA, while miR-708-3p usually exists as a passenger strand (miRNA*) and more studies focus on mir-708-5p as a guide-strand.…”

Circulating miRNAs: A New Opportunity in Bone Fragility

“…The same research team [ 80 ] identified four upregulated miRNAs (miR-708-5p, miR-34b-5p, miR-3161, and miR-328-5p) and two downregulated miRNAs (miR-4422 and miR-939-3p) in monocytes isolated from peripheral blood of seven OP patients, compared with seven HC, by using small RNA-sequencing. Following qPCR validation, only miR-708-5p was found significantly upregulated in OP women.…”

circRNA Expression Profile in Dental Pulp Stem Cells during Odontogenic Differentiation

“…Interestingly, some of the miRNAs detected in this network have been already demonstrated to regulate differentiation processes. For instance, it has been reported that, in peripheral blood monocytes, miR-708-5p can negatively regulate the expression level of factors involved in bone metabolism such as AKT1, AKT2, PARP1 FKBP5, and MP2K3, resulting in an osteoporotic phenotype [ 39 ]. Moreover, the lncRNA HIF1A-AS2 can competitively bind miR-665 and thus positively regulates IL6, activating the PI3K/Akt signaling pathway, which promotes osteogenic differentiation of adipose-derived stem cells [ 40 ].…”