Up-Regulation of TGF-β Promotes Tendon-to-Bone Healing after Anterior Cruciate Ligament Reconstruction using Bone Marrow-Derived Mesenchymal Stem Cells through the TGF-β/MAPK Signaling Pathway in a New Zealand White Rabbit Model

Abstract

Background/Aims: This study aimed to explore the role of TGF-β in tendon-to-bone healing after anterior cruciate ligament (ACL) reconstruction using bone marrow-derived mesenchymal stem cells (BMSCs) through the TGF-β/MAPK signaling pathway in a New Zealand white rabbit model. Methods: A total of 72 healthy male New Zealand white rabbits were selected for these experiments. Flow cytometry and immunofluorescence were used to detect the expression of BMSC surface markers, and qRT-PCR was performed to detect TGF-β mRNA expression. The ACL reconstruction model was established with autografts. The rabbits were randomly divided into the following groups: inhibition of TGF-β (inhibition), over-expression of TGF-β (over-expression), empty vector and untreated (n = 18 per group). Hematoxylineosin (HE) staining, toluidine blue staining and Masson trichrome staining were conducted to observe any chondrocyte-like cell growth, and biomechanical tests were used to calculate the maximum load and rigidity. Three-dimensional CT imaging and Western blotting were applied to detect changes in bone tunnel size and bone density and the expression levels of TGF-β/MAPK signaling pathway-related proteins, respectively. Results: CD90 and CD44 were positively expressed, while CD11b was not detected. Compared with the empty vector and untreated groups, TGF-β mRNA expression was significantly decreased in the inhibition group but increased in the over-expression group; the latter group had a larger number of fibroblasts, a tighter tendon-bone interface, an increased number of chondrocyte-like cells and fibrochondrocytes, and more collagen fibers than the inhibition, empty vector and untreated groups. Compared with the empty vector and untreated groups, the maximum load and rigidity; the CT values of bone tunnel and bone tunnel margin; and the protein expression levels of TGF-β, p-ERK1/2, p-p38, p-JNK, c-jun and c-myc were significantly down-regulated in the inhibition group but up-regulated in the over-expression group. Conclusion: Our study indicated that up-regulating TGF-β expression in BMSCs from New Zealand white rabbits could promote tendon-to-bone healing after ACL reconstruction by regulating the TGF-β/MAPK signaling pathway.

Impact of history of periodontitis on gene expression of bone-related factors in young patients

“…TGF-β is an important growth factor known to participate in the formation of several tissues through production of extracellular proteins, regulation of matrix metalloproteinases, and proliferation of fibroblasts during the wound healing process, including in bone. 20,21,22 TGF-β may be involved in callus formation, osteoclast apoptosis, and inhibition of osteoclast activation. 20,23,24 Produced by platelets, chondrocytes and osteoblasts, TGF-β is released during bone turnover and regeneration, and can be deposited in the bone matrix, where it stimulates proliferation of mesenchymal stem cells, preosteoblasts, chondrocytes, and osteoblasts.…”

Enhancement of tendon‑bone healing following rotator cuff repair using hydroxyapatite with TGFβ1

“…Kovacevic et al ( 22 ) combined TGFβ3 with an injectable Ca-P matrix and demonstrated that it may improve healing following rotator cuff repair. A recent study demonstrated that upregulating TGFβ expression in bone mesenchymal stem cells (BMSCs) can promote tendon-to-bone healing following ACL reconstruction by regulating the TGFβ1 mitogen-activated protein kinase (MAPK) 1 signaling pathway ( 23 ). In addition, TGFβ1 is the most important fibrosis inducer ( 24 ), which could explain the increase in collagen fibers.…”

FGF-2-Induced Human Amniotic Mesenchymal Stem Cells Seeded on a Human Acellular Amniotic Membrane Scaffold Accelerated Tendon-to-Bone Healing in a Rabbit Extra-Articular Model

“…Many growth factors have been discovered and applied to tissue engineering technology, including transforming growth factor-β (TGF-β) [27], epidermal growth factor (EGF) [28], vascular endothelial growth factor (VEGF) [29], and fibroblast growth factor (FGF) [30]. Among them, FGF-2 (basic fibroblast growth factor) has been widely used in tissue engineering technology due to its unique advantages [31].…”