WITHDRAWN: Exosomes Derived from Bone Marrow Mesenchymal Stem Cell Preconditioned by Low-Intensity Pulsed Ultrasound Stimulation Promote Bone-Tendon Interface Fibrocartilage Regeneration and Ameliorate Rotator Cuff Fatty Infiltration

Abstract

Fibrovascular scar healing of bone-tendon interface (BTI) instead of functional fibrocartilage regeneration is the main concern associated with unsatisfactory prognosis in rotator cuff repair. Mesenchymal stem cells exosomes have been reported to be a new promising cell-free approach for rotator cuff healing. Whereas, controvercies abound in whether exosomes of native MSCs alone can effectively induce chondrogenesis. In this study, we aimed to explore the effect of Exosomes derived from low-intensity pulsed ultrasound stimulation (LIPUS)-preconditioned bone marrow mesenchymal stem cells (LIPUS-BMSC-Exos) or un-preconditioned BMSCs (BMSC-Exos) on rotator cuff healing and the underlying mechanism. Specifically, C57BL/6 mice underwent unilateral supraspinatus tendon detachment and repair were randomly assigned to saline, BMSCs-Exos or LIPUS-BMSC-Exos injection therapy. The results indicated that the biomechanical properties of the supraspinatus tendon-humeral junction were significantly improved in the LIPUS-BMSC-Exos group than that of the BMSCs-Exos group. The LIPUS-BMSC-Exos group also exhibited a higher histological score and more newly regenerated fibrocartilage at the repair site at postoperative 2 and 4 weeks and less fatty infiltration at 4 weeks than the BMSCs-Exos group. In vitro, co-culture of BMSCs with LIPUS-BMSC-Exos could significantly promote BMSCs chondrogenic differentiation and inhibit adipogenic differentiation than the BMSCs and BMSC-Exos co-cultured group did. Subsequently, quantitative real-time polymerase chain reaction revealed significantly higher enrichment of chondrogenic miRNAs and less enrichment of adipogenic miRNAs in LIPUS-BMSC-Exos compared with BMSC-Exos. Moreover, we demonstrated that this chondrogenesis-inducing potential was primarily attributed to miR-140, one of the most abundant miRNAs in LIPUS-BMSC-Exos. Collectively, our results highlight the regenerative potential of LIPUS-BMSC-Exos to promote BTI fibrocartilage regeneration and ameliorate supraspinatus fatty infiltration by positive regulation of pro-chondrogenetic and anti-adipogenetic of BMSCs differentiation which was primarily through delivering miR-140.

Therapeutic Potential of Exosomes in Tendon and Tendon–Bone Healing: A Systematic Review of Preclinical Studies

“…Forty-five articles were included after screening and all of them were case–control studies [ 8 , 9 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 86 , 87 , 88 , 89 , 90 ]. Another article was included by searching the references of the included articles and review articles related to the topic [ 85 ]. Finally, 46 studies were included for synthesis.…”

“…All studies had a low risk of baseline characteristics under selection bias, random outcome assessment under detection bias, attrition bias, reporting bias, and other biases [ 8 , 9 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 ]. All studies reported baseline characteristics of the animals used which included the species, age and gender of the animals, and the outcomes were randomly assessed [ 8 , 9 , 47 , 48 , 49 , 50 , 51 , 52 ,…”

“…All studies reported baseline characteristics of the animals used which included the species, age and gender of the animals, and the outcomes were randomly assessed [ 8 , 9 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 ]. Therefore, all studies were assigned low risk for baseline characteristics and random outcome assessment [ 8 , 9 , 47 , 48 , 49 , 50 , 51 , 52 , 53 ,…”

“…Exosomes have been reported to play an effective therapeutic role in a variety of cancers [ 42 , 43 , 44 ], neurological diseases [ 45 ] and acute organ injuries [ 46 ]. In recent years, exosomes have also been proven to promote tendon and tendon–bone healing [ 8 , 9 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 ].…”

Therapeutic potential and mechanisms of mesenchymal stem cell-derived exosomes as bioactive materials in tendon–bone healing

“…Furthermore, Feng et al discovered that exosomes derived from genetically modified Scleraxis-overexpressing PDGFRα(+) BMMSCs delivered miR-6924–5p to prevent osteoclast formation during tendon–bone healing and enhance the biomechanical strength of the TBI [ 89 ]. A recent study conducted by Wu et al found that exosomes derived from low-intensity pulsed ultrasound stimulation (LIPUS)-preconditioned bone marrow mesenchymal stem cells (LIPUS-BMSC-Exos) could improve fibrocartilage regeneration at the tendon–bone interface and decrease supraspinatus fatty infiltration in a murine RC repair model by promoting BMSC chondrogenesis and anti-adipogenesis, which was primarily by delivering miR-140 [ 90 ]. Similarly, Z. Li et al demonstrated that BMSC-derived exosomes (BMSC-Exos) overexpressing miR-23a-3p could promote M1 macrophage to M2 macrophage polarization, reduce the early inflammatory reaction at the tendon–bone interface, and promote early healing after ACL reconstruction [ 91 ].…”