Adiponectin Promotes Human Jaw Bone Marrow Stem Cell Osteogenesis

Abstract

Human jaw bone marrow mesenchymal stem cells (h-JBMMSCs) are multipotent progenitor cells with osteogenic differentiation potential. The relationship between adiponectin (APN) and the metabolism of h-JBMMSCs has not been fully elucidated, and the underlying mechanism remains unclear. The aim of the study was to investigate the effect and mechanism of APN on h-JBMMSC metabolism. h-JBMMSCs were obtained from the primary culture of human jaw bones and treated with or without APN (1 µg/mL). Osteogenesis-related gene expression was evaluated by real-time polymerase chain reaction (PCR), alkaline phosphatase (ALP) activity assay, and enzyme-linked immunosorbent assay (ELISA). To further investigate the signaling pathway, mechanistic studies were performed using Western blotting, immunofluorescence, lentiviral transduction, and SB202190 (a specific p38 inhibitor). Alizarin Red staining showed that APN promoted h-JBMMSC osteogenesis. Real-time PCR, ALP assay, and ELISA showed that ALP, osteocalcin (OCN), osteopontin, and integrin-binding sialoprotein were up-regulated in APN-treated cells compared to untreated controls. Immunofluorescence revealed that adaptor protein containing a pleckstrin homology domain, phosphotyrosine domain, and leucine zipper motif (APPL1) translocated from the nucleus to the cytoplasm with APN treatment. Additionally, the phosphorylation of p38 mitogen-activated protein kinase (MAPK) increased over time with APN treatment. Moreover, knockdown of APPL1 or p38 MAPK inhibition blocked the expression of APN-induced calcification-related genes including ALP, Runt-related transcription factor 2 (RUNX2), and OCN. Furthermore, Alizarin Red staining of calcium nodes was not increased by the knockdown of APPL1 or p38 inhibition. Our data suggest that this regulation is mediated through the APPL1-p38 MAPK signaling pathway. These findings collectively provide evidence that APN induces the osteogenesis of h-JBMMSCs through APPL1-mediated p38 MAPK activation.

Adiponectin promotes human jaw bone marrow mesenchymal stem cell chemotaxis via CXCL1 and CXCL8

“…APN has already been reported to activate the adenosine monophosphate‐activated protein kinase (AMPK) signalling pathway by binding with the membrane receptor AdipoR1 . In addition, the results from our present study confirmed that APN could promote the osteogenesis of h‐JBMMSCs through the APPL1‐p38 MAPK signalling pathway . The AMPK and p38 MAPK pathways are both important signalling nodes capable of regulating cellular metabolism and participate in various life processes.…”

“…The informed consent was obtained from all the patients. The h‐JBMMSCs were obtained from patients undergoing orthognathic surgery and were identified based on positivity for CD73, CD90 and CD105 and negativity for CD34, CD11b, CD19, CD45 and HLA‐DR using flow cytometry . The osteoblast‐inducing conditional medium consisted of α‐MEM medium with 10% FBS, 10 nM dexamethasone, 10 mM β‐glycerophosphate and 50 μg/ml L‐ascorbic acid (Sigma‐Aldrich, St. Louis, MO, USA).…”

“…In our previous study, we showed that APN could promote the osteogenesis of extraction sockets of beagle dogs in vivo . In another in vitro study, APN was found to promote the osteogenesis of human jaw bone mesenchymal stem cells (h‐JBMMSCs) through the APPL1‐p38 MAPK signalling pathway . Bone regeneration in response to bioactive molecules requires the recruitment, proliferation and osteogenic differentiation of mesenchymal progenitors .…”

Adiponectin regulates BMSC osteogenic differentiation and osteogenesis through the Wnt/β-catenin pathway

“…Pu et al . found that ApN can promote human jaw bone marrow mesenchymal stem cell osteogenesis through the APPL1-mediated p38 MAPK pathway and increase ossification-related gene expression levels 27 . However, very few studies have investigated the association between ApN and the Wnt/β-catenin pathway, one of the most important pathways in osteogenesis, with respect to the regulation of bone formation and BMSC osteogenic differentiation.…”

“…found that sustained ApN release can promote peri-implant osteogenesis in ovariectomization rabbits by suppressing osteoclasts 18 . ApN can increase bone mass by suppressing osteoclastogenesis and bone resorption 19, 20 , stimulating local angiogenesis 21, 22 , or promoting osteogenic differentiation 19, 23–27 . Several osteogenesis signalling pathways have been found to be activated in the presence of ApN; however, few studies have discussed the relevance of ApN and the Wnt/β-catenin pathway with respect to osteogenesis.…”