Shockwave Treatment Enhances the Extracellular Matrix Production in Articular Chondrocyte Through Activation of the ROS/MAPK/Nrf2 Signaling Pathway.
Background: Shockwaves are acoustic pulses that have been widely used in the management of musculoskeletal disease. In current study, we investigated the biological effect of shockwaves on articular chondrocytes and clarified the mechanism by which chondrocytes sense and respond to the mechanical stimulation of shockwave treatment.
Methods: Porcine articular chondrocytes and human osteoarthritis (OA) chondrocytes were cultured in a three-dimensional pellet culture model and subjected to shockwaves. Then alamarBlue assay, Hoechest DNA assay, fluorescence-activated cell sorter, real-time polymerase chain reaction immunofluorescence staining, and western blotting were used to determine biological function and signaling transduction of chondrocytes after shockwaves.
Results: Shockwaves increased the sulfated glycosaminoglycan (GAG), Col2a1, and Acan production of chondrocytes without affecting cell viability and proliferation. Furthermore, shockwaves increased transient reactive oxygen species (ROS) production primarily through the action of xanthine oxidase and subsequently through phosphorylation of Erk1/2 and p38. Shockwaves also activated the nuclear translocation of Nrf2 and the Nrf2-related downstream gene expression of Ho-1 and Nqo-1. We suppressed the xanthine oxidase activity by allopurinol or specific siRNA, which significantly abrogated shockwave-induced mitogen-activated protein kinase (MAPK) phosphorylation, Nrf2 nuclear translocation, and extracellular matrix (ECM) synthesis. U0126 and SB203580, the specific inhibitors of MAPKs MEK1/2 and p38, respectively, significantly abolished shockwave-induced Nrf2 nuclear translocation and ECM synthesis. Inhibition of Nrf2 by both shRNA knockdown and brusatol reduced the shockwave-increased GAG, Col2a1, and Acan production.
Conclusions: Maintaining the homeostasis of the ECM of the articular cartilage is crucial for preventing the development OA. Our data indicate that shockwaves enhanced the ECM synthesis of chondrocytes through the activation of the ROS/MAPK/Nrf2 signaling axis. This study demonstrates that shockwaves holds promising therapeutic potential for OA and provides fundamental evidence for developing an optimal therapeutic strategy.
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Posted 08 Jun, 2020
Shockwave Treatment Enhances the Extracellular Matrix Production in Articular Chondrocyte Through Activation of the ROS/MAPK/Nrf2 Signaling Pathway.
Posted 08 Jun, 2020
Background: Shockwaves are acoustic pulses that have been widely used in the management of musculoskeletal disease. In current study, we investigated the biological effect of shockwaves on articular chondrocytes and clarified the mechanism by which chondrocytes sense and respond to the mechanical stimulation of shockwave treatment.
Methods: Porcine articular chondrocytes and human osteoarthritis (OA) chondrocytes were cultured in a three-dimensional pellet culture model and subjected to shockwaves. Then alamarBlue assay, Hoechest DNA assay, fluorescence-activated cell sorter, real-time polymerase chain reaction immunofluorescence staining, and western blotting were used to determine biological function and signaling transduction of chondrocytes after shockwaves.
Results: Shockwaves increased the sulfated glycosaminoglycan (GAG), Col2a1, and Acan production of chondrocytes without affecting cell viability and proliferation. Furthermore, shockwaves increased transient reactive oxygen species (ROS) production primarily through the action of xanthine oxidase and subsequently through phosphorylation of Erk1/2 and p38. Shockwaves also activated the nuclear translocation of Nrf2 and the Nrf2-related downstream gene expression of Ho-1 and Nqo-1. We suppressed the xanthine oxidase activity by allopurinol or specific siRNA, which significantly abrogated shockwave-induced mitogen-activated protein kinase (MAPK) phosphorylation, Nrf2 nuclear translocation, and extracellular matrix (ECM) synthesis. U0126 and SB203580, the specific inhibitors of MAPKs MEK1/2 and p38, respectively, significantly abolished shockwave-induced Nrf2 nuclear translocation and ECM synthesis. Inhibition of Nrf2 by both shRNA knockdown and brusatol reduced the shockwave-increased GAG, Col2a1, and Acan production.
Conclusions: Maintaining the homeostasis of the ECM of the articular cartilage is crucial for preventing the development OA. Our data indicate that shockwaves enhanced the ECM synthesis of chondrocytes through the activation of the ROS/MAPK/Nrf2 signaling axis. This study demonstrates that shockwaves holds promising therapeutic potential for OA and provides fundamental evidence for developing an optimal therapeutic strategy.
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