AMD3100 Attenuates Post-Traumatic Osteoarthritis by Maintaining Transforming Growth Factor-β1-Induced Expression of Tissue Inhibitor of Metalloproteinase-3 via the Phosphatidylinositol 3-Kinase/Akt Pathway

Abstract

AMD3100 is a small-molecule inhibitor of the C-X-C motif chemokine ligand 12/C-X-C chemokine receptor type 4 (CXCL12/CXCR4) axis, while its role in aggrecan metabolism is unclear. We hypothesized that the AMD3100 modulates the transforming growth factor-b1 (TGF-b1)-induced expression of tissue inhibitor of metalloproteinase-3 (TIMP-3) in chondrocytes. We evaluated expression of CXCL12/CXCR4 and TIMP-3 in the knee joints of rats with and without osteoarthritis (OA) by immunohistochemistry, immunofluorescence, Western blotting, and enzyme-linked immunosorbent assay (ELISA). The rats were divided into sham control, destabilization of the medial meniscus/ AMD3100-treated (DMM/AMD3100-treated), and DMM/phosphate-buffered saline (PBS)treated groups. After 6 weeks, the rats were euthanized and subjected to histological and immunohistochemical analyses. Also, interleukin (IL)-1-pretreated primary chondrocytes were cultured in the presence of empty control (−, −), CXCL12a (+,−), CXCL12a + small interfering RNA (siRNA) CXCR4 (+,+), or CXCL12a + siNC (+NC), and the expression levels of target markers were evaluated by Western blotting and real-time reverse transcription PCR (RT-PCR). The CXCL12/CXCR4 levels were higher, and the expression of TIMP-3 was lower, in the OA rats compared to the healthy control rats. The rats in the DMM/AMD3100treated group revealed a markedly decreased immunological response and mild pathology. Treatment with CXCL12a increased expression of aggrecan and disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5) and suppressed that of TIMP-3 in IL-1-pretreated primary chondrocytes. TGF-b1 increased expression of TIMP-3, and this increase was reversed by CXCL12a via the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Moreover, these effects were inhibited by the CXCR4 antagonist

Molecular mechanisms of mechanical load-induced osteoarthritis

“…TGF-β maintains functions of articular cartilage by transducing Smad2/3P signals thereby promote collagen (Col2a1) and fibronectin (Fn1) synthesis and prevent the degradation of cartilage matrix induced by overload [48]. Moreover, TGF-β inhibits MMP13 activation by stimulating IL-2/12 [49]. It has also been reported that TGF-β inhibits cartilage matrix degradation by upregulating SOX9 signals.…”

Exogenous stromal cell-derived factor-1 (SDF-1) suppresses the NLRP3 inflammasome and inhibits pyroptosis in synoviocytes from osteoarthritic joints via activation of the AMPK signaling pathway

“…Based on these observations, we proposed a novel mechanism for SDF-1 in OA treatment. To the best of our knowledge, inhibitors of SDF-1 (such as AMD3100) have been previously reported to ameliorate degradation of OA cartilage (Lu et al 2019). However, our study represents the first report confirming that treatment of human OA-derived primary synoviocytes with SDF-1 has these beneficial effects.…”

Oxoglaucine mediates Ca2+ influx and activates autophagy to alleviate osteoarthritis through the TRPV5/calmodulin/CAMK‐II pathway

“…The rat model of OA was prepared by destabilization of the medial meniscus (DMM), as previously described (Geng et al, 2020; Iijima et al, 2014; Lu et al, 2019; Moon et al, 2018; Mwangi et al, 2018). Four weeks after surgery, the rats were injected intra‐articularly with 0.1‐ml normal saline or HA or oxoglaucine (40 ng ml −1 ) or oxoglaucine (40 ng ml −1 ) and D3 (10 −8 mol L −1 ) or oxoglaucine (40 ng ml −1 ) and 3‐MA (5 mM) two times a week.…”

“…Human OA chondrocytes were infected with adenoviral vectors containing GFP-mRFP-LC3 (GenechemCo., Ltd, Shanghai, China) for 8 h. After treatment with oxoglaucine (40 ng ml À1 ) or oxoglaucine (40 ng ml À1 ) + 3-methyladenine (3-MA; 5 mM) for 24 h, these cells were observed under a confocal microscope (Nikon A1, Japan) to calculate the number of yellow and green dots for evaluating autophagic influx (Chen et al, 2012). The rat model of OA was prepared by destabilization of the medial meniscus (DMM), as previously described (Geng et al, 2020;Iijima et al, 2014;Lu et al, 2019;Moon et al, 2018;Mwangi et al, 2018). Four weeks after surgery, the rats were injected intraarticularly with 0.1-ml normal saline or HA or oxoglaucine (40 ng ml À1 ) or oxoglaucine (40 ng ml À1 ) and D3 (10 À8 mol L À1 ) or oxoglaucine (40 ng ml À1 ) and 3-MA (5 mM) two times a week.…”