Long noncoding RNAs: a missing link in osteoporosis

Figures

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  Fig. 1. Long noncoding RNA are crucial mediators of the bone remodeling process, which is disrupted in osteoporosis

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  Fig. 2. Long noncoding RNAs act as inhibitors (a) or promoters (b) of osteogenic differentiation process. lncRNAs are key transcriptional and translational regulators that may act mainly as modulators of chromatin architecture, as ligands to activators/repressors of gene promoters, as source transcripts to other regulatory RNAs, and as competing endogenous RNAs to pro-osteogenic microRNAs (green circles) and anti-osteogenic microRNAs (red circles), controlling the expression of protein-coding genes implicated in osteogenic differentiation by different mechanisms

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  Fig. 3. Differently expressed long noncoding RNAs in blood samples are potential biomarkers for osteoporosis

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  Fig. 4. Single-nucleotide polymorphisms in long noncoding RNAs are associated with bone mineral density and osteoporosis risk

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  Fig. 5. A potential delivery strategy for long noncoding RNA (lncRNA) is proposed. Extracellular vesicles (EV) are naturally secreted by cells and contain proteins, DNA, and RNA. Exogenous lncRNA capable to promote bone formation and inhibit bone resorption can be encapsulated into EV, which can be used as natural delivery vehicles. In vivo delivery of lncRNA-loaded EV can be systemic through intravenous, intraperitoneal, oral or nasal routes, or local through EV encapsulation into scaffolds, which might help to promote local bone repair upon fragility fractures