RETRACTED ARTICLE: Effects of miR-672 on the angiogenesis of adipose-derived mesenchymal stem cells during bone regeneration

Abstract

Background Sufficient vascular network plays an important role in the repair of bone defects. Bone morphogenetic protein 2 (BMP2) being a key regulator of angiogenesis has attracted the attention of researchers. In addition, evidence has suggested that BMP2 coordinates with microRNAs (miRNAs) to form intracellular networks regulating mesenchymal stem cells (MSCs) angiogenesis. Elucidating the underlying mechanisms that are regulating adipose-derived mesenchymal stem cells (ADSCs) angiogenesis might provide more effective method to enhance bone regeneration. Methods We identified the specific miRNA in rat ADSCs during BMP2-induced angiogenesis and chose the most significant differentially expressed miRNA, miR-672. Three lentiviral system named Lenti-miR-672, Lenti-as-miR-672, and Lenti-miR-NC were transduced into the ADSCs individually. Then, the quantitative real-time polymerase chain reaction (qPCR), western blotting, and blood vessel formation analysis were performed to investigate the effects of miR-672 on ADSCs angiogenesis. Bioinformation platforms were used to screen the potential target of miR-672. Small interfering RNA (siRNA) against TIMP2 (si-TIMP2) mRNA were obtained from GenePharma, and then si-TIMP2 miRNA and miR-672 were co-transfected into ADSCs to detect the effects of TIMP2 on angiogenesis. Calcium phosphate cement (CPC) scaffolds that seeded the lentiviral-modified ADSCs were constructed to test the vascularized bone regeneration in vivo. Results Our data showed that after the angiogenesis of ADSCs induced by BMP2, miR-672 was the most significantly upregulated miRNA. Overexpression of miR-672 promoted the angiogenesis of ADSCs, while knockdown of miR-672 repressed the angiogenesis of ADSCs. The bioinformation prediction showed that TIMP2 might be the one of miR-672′ potential targets. TIMP2 protein expression was gradually decreased in ADSCs with overexpressed miR-672. And the angiogenic factors were upregulated in the ADSCs which were transduced with si-TIMP2. Then, the CPC scaffolds coupled the miR-672-modified ADSCs and showed the good potential in vascularized bone regeneration. The overexpressed miR-672 could greatly enhance the blood vessel volume and Microfil-labeled blood vessel numbers in newly formed bone. Conclusion BMP2 could promote the angiogenesis of ADSCs through stimulating the expression of miR-672 in ADSCs. miR-672 acted as a positive regulator on the angiogenesis of ADSCs, and incorporating the miR-672-modified ADSCs in the CPC could significantly promote the vascularization and the bone regeneration.

Advanced strategies of scaffolds design for bone regeneration

“…Many approaches have been explored to prepare gene and interfering RNA-activated scaffolds for bone tissue engineering, including activating scaffolds with plasmid DNA, [76] small interfering RNA, [97][98][99] and micro-RNA. [100][101][102] As a means to overcome the biological barrier, bisphosphonate lipid-like materials with a high affinity for bone minerals could effectively deliver mRNA therapeutics to the bone microenvironment in vivo (Figure 6a). [103] In the studies regarding the bone-homing ability of BP-LNPs, an in vivo imaging system was adopted to track their biodistribution.…”

DNAJC2 is reversely regulated by miR‑627‑3p, promoting the proliferation of colorectal cancer

“…However, its expression, function and mechanism in CRC remains to be elucidated. Overexpression of miR-672 could promote the angiogenesis of adipose-derived mesenchymal stem cells by suppressing tissue inhibitor of metalloproteinase 2 (20). miR-672 also induces osteoblast differentiation and mineralization through inhibition of Smad ubiquitin regulatory factor 1 with enhanced Runt-related transcription factor 2 transcriptional activation in mice (21).…”

Strategies for Enhancing Vascularization of Biomaterial‐Based Scaffold in Bone Regeneration

“…[56] Another trial confirmed the in vitro angiogenic potential of ADSC induced by BMP-2, and the evaluation of micro-RNA engineered ADSC incorporated on a scaffold; for osteoinduction. [57] These studies, successfully denote the efficacy of ADSC in stimulating vessel formation and healing bone defects as well ease of clinical applicability, procurement, and minimum complications at the donor site. The use of stromal vascular fraction (SVF) has been suggested in scaffolds in a clinical study, which figuratively expresses the percent of ADSC and SVF in a fraction of aspirate as 32 % and 4.28 % respectively; when compared to the BMSC components.…”

“…The advantage of preferring co‐cultures of ADSC and EPC, human microvascular endothelial cells (HMECs) warrant better vasculature [56] . Another trial confirmed the in vitro angiogenic potential of ADSC induced by BMP‐2, and the evaluation of micro‐RNA engineered ADSC incorporated on a scaffold; for osteoinduction [57] . These studies, successfully denote the efficacy of ADSC in stimulating vessel formation and healing bone defects as well ease of clinical applicability, procurement, and minimum complications at the donor site.…”