Ectopic Cartilage Formation Induced by Mesenchymal Stem Cells on Porous Gelatin-Chondroitin-Hyaluronate Scaffold Containing Microspheres Loaded with TGF-β1

Abstract Background: Tendon injury is a common but tough medical problem. Unsatisfactory clinical results have been reported in tendon repair using mesenchymal stem cells (MSCs) therapy, creating a need for a better strategy to induce MSCs to tenogenic differentiation. This study was designed to investigate the role of hypoxia in the tenogenic differentiation of MSCs in vitro and in vivo and to compare the tenogenic differentiation capacities of different MSCs under hypoxia condition in vitro. Methods: Adipose tissue-derived MSCs (AMSCs) and bone marrow-derived MSCs (BMSCs) were isolated and characterized by the expression of MSC-specific markers and tri-lineage differentiation. The expression of hypoxia induced factor-1 alpha (Hif-1α) and the proliferation of AMSCs and BMSCs were examined in order to confirm the establishment of hypoxia condition. qRT-PCR, western blot, and immunofluorescence staining were used to evaluate the expression of tendon-associated marker Col-1a1, Col-3a1, Dcn, and Tnmd in AMSCs and BMSCs under hypoxia and/or Tgf-β1 condition. In vivo, a patellar tendon injury model was established. Normoxic and hypoxic BMSCs were cultured and implanted. Histological, biomechanical and transmission electron microscopy analyses were performed to assess the improved healing effect of hypoxic BMSCs on tendon injury. Results: Hypoxia remarkably increased the expression of Hif-1α and the proliferation of AMSCs and BMSCs. Our in vitro results detected that hypoxia not only promoted a significant increase in tenogenic markers in both AMSCs and BMSCs compared with the normoxia group, but also showed higher inductility compared with Tgf-β1. In addition, hypoxic BMSCs exhibited higher potential of tenogenic differentiation than hypoxic AMSCs. Our in vivo results demonstrated that hypoxic BMSCs possessed better histological and biomechanical properties than those of normoxic BMSCs, as evidenced by histological scores, quantitative analysis of immunohistochemical staining for Col-1a1 and Tnmd, the range and average of collagen fibril diameters and patellar tendon biomechanical tests. Conclusions: These findings suggested that hypoxia may be a practical and reliable strategy to induce tenogenic differentiation of BMSCs for tendon repair and could enhance the effectiveness of MSCs therapy in treating tendon injury.

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TGF-β1-containing exosomes derived from bone marrow mesenchymal stem cells promote proliferation, migration and fibrotic activity in rotator cuff tenocytes

Regenerative Therapy ◽

10.1016/j.reth.2020.07.001 ◽

2020 ◽

Vol 15 ◽

pp. 70-76

Author(s):

Jia Li ◽

Zheng-Peng Liu ◽

Cong Xu ◽

Ai Guo

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Mesenchymal Stem Cells ◽

Rotator Cuff ◽

Marrow Mesenchymal Stem Cells ◽

Tgf Β1

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Microparticles derived from human erythropoietin mRNA-transfected mesenchymal stem cells inhibit epithelial-to-mesenchymal transition and ameliorate renal interstitial fibrosis

Stem Cell Research & Therapy ◽

10.1186/s13287-020-01932-z ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Mirae Lee ◽

Seok-hyung Kim ◽

Jong Hyun Jhee ◽

Tae Yeon Kim ◽

Hoon Young Choi ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Epithelial To Mesenchymal Transition ◽

Transforming Growth Factor ◽

Mdck Cells ◽

Mesenchymal Transition ◽

Human Erythropoietin ◽

Renal Tubulointerstitial Fibrosis ◽

Tgf Β1 ◽

E Cadherin

Abstract Background Renal tubulointerstitial fibrosis (TIF) plays an important role in the progression of chronic kidney disease (CKD) and its pathogenesis involves epithelial-to-mesenchymal transition (EMT) upon renal injury. Recombinant human erythropoietin (rhEPO) has been shown to display novel cytoprotective effects, in part by inhibiting transforming growth factor (TGF)-β1-induced EMT. Here, we evaluated the inhibitory effects of microparticles (MPs) derived from human EPO gene-transfected kidney mesenchymal stem cells (hEPO-KMSCs) against TGF-β1-induced EMT in Madin-Darby canine kidney (MDCK) cells and against TIF in mouse kidneys with unilateral ureteral obstruction (UUO). Methods EMT was induced in MDCK cells by treatment with TGF-β1 (5 ng/mL) for 48 h and then inhibited by co-treatment with rhEPO (100 IU/mL), mock gene-transfected KMSC-derived MPs (MOCK-MPs), or hEPO-KMSC-derived MPs (hEPO-MPs) for a further 48 h. UUO was induced in FVB/N mice, which were then treated with rhEPO (1000 IU/kg, intraperitoneally, every other day for 1 week), MOCK-MPs, or hEPO-MPs (80 μg, intravenously). Alpha-smooth muscle actin (α-SMA), fibronectin, and E-cadherin expression were evaluated in MDCK cells and kidney tissues, and the extent of TIF in UUO kidneys was assessed by immunohistochemical staining. Results TGF-β1 treatment significantly increased α-SMA and fibronectin expression in MDCK cells and decreased that of E-cadherin, while co-treatment with rhEPO, MOCK-MPs, or hEPO-MPs markedly attenuated these changes. In addition, rhEPO and hEPO-MP treatment effectively decreased phosphorylated Smad2 and Smad3, as well as phosphorylated p38 mitogen-activated protein kinase (MAPK) expression, suggesting that rhEPO and rhEPO-MPs can inhibit TGF-β1-induced EMT via both Smad and non-Smad pathways. rhEPO and hEPO-MP treatment also significantly attenuated the extent of renal TIF after 1 week of UUO compared to MOCK-MPs, with hEPO-MPs significantly reducing myofibroblast and F4/80+ macrophage infiltration as well as EMT marker expression in UUO renal tissues in a similar manner to rhEPO. Conclusions Our results demonstrate that hEPO-MPs modulate TGF-β1-induced EMT in MDCK cells via the Smad2, Smad3, and p38 MAPK pathways and significantly attenuated renal TIF in UUO kidneys.

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