The circulatory levels and bone expression of MIR21, 34a, 155 and their target genes in a section of Egyptian Population

Bone tissue is constantly regenerated and repaired through a finely balanced process known as bone remodeling. Many miRNAs act as regulators of the signaling pathways involved in bone metabolic processes to maintain tissue homeostasis. This study aimed to assess the circulating levels of MIR21, MIR34a, and MIR155 in human serum and their bone expression, and the expression of bone turnover-related genes which can reflect the bone quality. This prospective study was conducted on 60 patients (30 males and 30 females) indicated for surgical interventions for neural decompression +/- fixation. Relative quantification of expression of MIR21, miR34a, and MIR155 and bone related genes was assayed using PCR. The serum levels of osteocalcin and Serum Bone Alkaline Phosphatase (sBAP) were assayed using a human ELISA kit. The main finding of the present work was the strong positive association between the circulating levels of only miR21 and MIR155 and their bone expression in the population under study and with bone markers and target genes Also, a positive association was found between both bone expression and circulating MIR21 levels with age and sBAP. These results suggest that the circulating levels of these microRNAs as early markers for the predication of bone quality.