Characterization of microRNA expression profiles in normal and osteoarthritic human chondrocytes

Abstract

BackgroundOsteoarthritis (OA) is a multifactorial disease characterized by destruction of the articular cartilage due to environmental, mechanical and genetic components. The genetics of OA is complex and is not completely understood. Recent works have demonstrated the importance of microRNAs (miRNAs) in cartilage function. MiRNAs are a class of small noncoding RNAs that regulate gene expression and are involved in different cellular process: apoptosis, proliferation, development, glucose and lipid metabolism. The aim of this study was to identify and characterize the expression profile of miRNAs in normal and OA chondrocytes and to determine their role in the OA.MethodsChondrocytes were moved to aggregate culture and evaluated using histological and qPCR techniques. miRNAs were isolated and analyzed using the Agilent Human miRNA Microarray.ResultsOf the 723 miRNAs analyzed, 7 miRNAs showed a statistically significant differential expression. Amongst these 7 human miRNAs, 1 was up-regulated in OA chondrocytes (hsa-miR-483-5p) and 6 were up-regulated in normal chondrocytes (hsa-miR-149*, hsa-miR-582-3p, hsa-miR-1227, hsa-miR-634, hsa-miR-576-5p and hsa-miR-641). These profiling results were validated by the detection of some selected miRNAs by qPCR. In silico analyses predicted that key molecular pathways potentially altered by the miRNAs differentially expressed in normal and OA chondrocytes include TGF-beta, Wnt, Erb and mTOR signalling; all of them implicated in the development, maintenance and destruction of articular cartilage.ConclusionsWe have identified 7 miRNAs differentially expressed in OA and normal chondrocytes. Our potential miRNA target predictions and the signalling cascades altered by the differentially expressed miRNAs supports the potential involvement of the detected miRNAs in OA pathology. Due to the importance of miRNA in mediating the translation of target mRNA into protein, the identification of these miRNAs differentially expressed in normal and OA chondrocyte micropellets could have important diagnostic and therapeutic potential. Further studies are needed to know the function of these miRNAs, including the search of their target mRNA genes, which could lead to the development of novel therapeutic strategies for the OA treatment.

WNT3A gene polymorphisms are associated with bone mineral density variation in postmenopausal mestizo women of an urban Mexican population: findings of a pathway-based high-density single nucleotide screening

“…bjmu.edu.cn/mirsnp) predicted that rs752107 disrupt a binding site for miR-149. This miRNA has been reported to be highly expressed in osteoarthritis samples, a disease with a high BMD phenotype (Díaz-Prado et al 2012). It can be speculated that miR-149 may bind tightly to WNT3A mRNA transcripts containing the C allele, and thus negatively regulate WNT3A protein translation.…”

miR-1247 Functions by Targeting Cartilage Transcription Factor SOX9

“…The validity of our approach is further supported by the presence, in our list of candidates, of several miRNAs whose role in cartilage has already been demonstrated. Thus, miR-140 has been shown to be key for cartilage development and homeostasis (7); miR-221-3p regulates chondrogenic differentiation by targeting Mdm2 (35); miR-145 targets master transcription factor SOX9 in HACs (14); and the expression of several other miRNAs identified (miR-137, miR34a-5p, miR-337-5p, miR-342-3p, miR-210, miR-195-5p, miR-483-5p, miR-146a-5p, or miR-140-5p) is altered in osteoarthritis (11,36,37). Interestingly, some of the selected miRNAs are clustered in the genome (such as miR-654-5p and miR-543 or miR-143-3p and miR-145-5p) or are processed from the same pre-miRNA (such as miR-140-5p and miR-140-3p or miR34a-5p and miR-34a-3p), indicating that common regulatory networks may be affecting their expression during cartilage differentiation.…”

MicroRNAs and post-transcriptional regulation of skeletal development

“…At present, therapy is usually based on symptomatic treatment, mainly using nonsteroidal anti-inflammatory drugs (NSAIDs), but these fail to slow articular degeneration and disease progression. Studies on OA have demonstrated that miRNA expression is regulated during this process, indicating the possibility of future miRNA therapies (Iliopoulos et al 2008, Jones et al 2009, Akhtar et al 2010, Diaz-Prado et al 2012. One of the main characteristics of osteoarthritic chondrocytes is the secretion of the pro-inflammatory cytokines interleukin 1b (IL1b) and TNFa.…”