Emerging roles of circular RNAs in osteoporosis

Abstract

Osteoporosis is one bone disease characterized with skeletal impairment, bone strength reduced and fracture risk enhanced. The regulation processes of bone metabolism are associated with several factors such as mechanical stimulation, epigenetic regulation and hormones. However, the mechanism of osteoporosis remains unsatisfactory. Increasing high-throughput RNA sequencing and circular RNAs (circRNAs) microarray studies indicated that circRNAs are differentially expressed in osteoporosis. Growing functional studies further pinpointed specific deregulated expressed circRNAs (e.g., circ_28313, circ_0016624, circ_0006393, circ_0076906 and circ_0048211) for their functions involved in bone metabolism, including bone marrow stromal cells (BMSCs) differentiation, proliferation and apoptosis. Moreover, CircRNAs (circ_0002060, Circ_0001275 and Circ_0001445) may be acted as diagnostic biomarkers for osteoporosis. This review discussed recent progresses in the circRNAs expression profiling analyses and their potential functions in regulating BMSCs differentiation, proliferation and apoptosis.

Keywords: ceRNA; circRNAs; microRNA; osteoporosis.

FIGURE 1

miRNA, lncRNA and circRNA affect osteoblasts and osteoclasts and participate in the development of osteoporosis

FIGURE 2

Dysregulated circRNAs in osteoporosis. Until now, there are 34 circRNAs were upregulated and 31 circRNAs were downregulated in osteoporosis

FIGURE 3

circRNAs acts as biomarkers for osteoporosis. circ_0002060, circ_0001275, circ_0076690, circ_0001445 and circ_0021739 may be one potential biomarkers for osteoporosis

FIGURE 4

circRNAs regulated genes expression via sponging miRNAs in osteoporosis. Dysregulation expression of circRNA sponged related miRNAs expression and then regulating their target gene involved in the development of osteoporosis. Upper circRNAs represent upregulated in osteoporosis, while below circRNAs represent downregulated