Relationship between miRNA‑433 and SPP1 in the presence of fracture and traumatic brain injury

Abstract

Limb fracture combined with traumatic brain injury (TBI) is one of the most common multiple injuries and patients often suffer from severe craniocerebral injury combined with long bone fracture of the limbs. The present study examined the expression of osteopontin (SPP1) in the tibial fracture callus and heterotopic ossification tissues in craniocerebral injury and investigated its relationship with miR-433. A total of 26 patients with tibial fracture combined with brain injury were included in the TBI group, and 26 patients with simple tibial fracture were included in the control group. The patients received immobilization treatment and callus was collected during the operation. At the time of steel plate removal tissue ossification samples from patients with heterotopic ossification were collected. Peripheral blood was collected from all patients on the morning of the operation day. Expression of miR-433 and SPP1 mRNA was determined by reverse transcription-quantitative PCR and SPP1 protein expression was measured by western blotting. Dual luciferase reporter assay was used to identify the direct interaction between miR-433 and SPP1 mRNA. The human osteoblast line hFOB1.19 was transfected with agomiR-433 to overexpress miR-433 and expression of SPP1 was also examined. TBI enhanced the incidence of callus formation and heterotopic ossification in patients with fracture but did not alter fracture healing time. SPP1 mRNA and protein expression was elevated in patients who had tibial fracture in combination with craniocerebral injury in comparison with controls By contrast, expression of miR-433 was decreased in patients who had tibial fracture in combination with craniocerebral injury in comparison with controls. miR-433 regulated the expression of SPP1 mRNA and protein by directly binding to the 3'-untranslated region of SPP1 mRNA. The present study suggests that SPP1 mRNA and protein levels are increased in the callus, heterotopic ossification tissues and plasma from patients with tibial fracture combined with brain injury in comparison with controls. This elevation may be due to the reduced expression of miR-433.

Hu’po Anshen Decoction Accelerated Fracture-Healing in a Rat Model of Traumatic Brain Injury Through Activation of PI3K/AKT Pathway

“…Bone mineral density (BMD) is the main predictor of fracture healing, and bone microstructure is an important factor affecting bone strength. In this study, we observed bone healing by X-ray and bone microstructure by micro CT. Our results showed that TBI can promote callus formation, increase bone density and improve the bone microstructure around the fracture, which were consistent with previous reports ( Han et al, 2021 ). In addition, we also found that HPASD accelerated fracture healing in a concentration-dependent manner, which was also supported by the results of bone mechanical properties test and histological staining.…”

The role of miRNA and lncRNA in heterotopic ossification pathogenesis

“…In some of them, animal models of traumatic heterotopic ossification—Achilles tenotomy in mice [ 68 , 200 ] or specific muscle/chondrocytes cell lines were used [ 191 ]. Other studies included profiling of ncRNA in humans, including post-traumatic HO [ 113 , 173 ], patients after THA surgery [ 200 ] and NHO following CNS injury [ 189 ]. Of all published studies, the vast majority concerned only selected miRNA (miR-1, miR-19b-3p, miR-133a, miR-133b, miR-148a, miR-203, miR-206, miR 421, miR 433 and miR-630).…”

“…Most of the ones that were previously identified by bioinformatic analysis and shown to target specific elements of the HO signaling network elements, e.g., ACVR1/ALK2 [ 196 ], BMP2 [ 180 ]. Other miRNA studies aimed at targets such as Slug, which is the regulator of endothelial–mesenchymal transition [ 177 ], OPN/SSP1 mRNA [ 189 ] or PTEN that controls osteogenic differentiation of muscle cells [ 90 ]. Only a few studies analyzed the role of lncRNA in the pathogenesis of HO (lncRNA MIAT, lncRNA Mancr, and lncRNA CASC20) [ 42 , 199 , 200 ].…”

“…Most studies evaluated miRNAs and their impact on bone morphogenesis signaling, including canonical BMP [ 180 , 196 ] or WNT/β-catenin and MAPK pathways [ 68 ]. The expression of the osteogenesis master regulator RUNX2 [ 68 , 113 , 177 , 191 ] or levels of well-known osteogenic biomarkers, i.e., OCN [ 68 , 113 , 177 , 191 ], OPN/SSP1 [ 177 , 189 , 191 ], ALP [ 68 , 113 , 177 , 191 ], and BSP [ 68 ] or BMP2 [ 180 ] were assessed to determine effect of the miRNAs investigated. Similarly, studies in HO identified lncRNA (MIAT, Mancr, and CASC20) that aim for OSX [ 42 , 200 ] ALP [ 42 , 199 , 200 ], OCN [ 42 , 199 ], RUNX2 [ 42 , 199 , 200 ] as their effectors.…”

“…The expression of OPN/SPP1 is regulated, among others, by microRNAs, including miR433. This molecule affects the expression of OPN/SPP1 by direct binding to the 3′‑UTR of OPN/SPP1 mRNA [ 189 ]. In the case of patients with callus and HO in patients with traumatic brain injury (TBI), the expression of OPN/SPP1 increased significantly and miR433 was reduced, leading to increased accumulation of pro-inflammatory OPN/SPP1 protein in bone tissues and negatively affecting tibial fracture healing of tibial fractures [ 189 ].…”