MiRNA microarray in the synovial tissue 14 days after anterior cruciate ligament transection (ACLT)
Ontology highlight
ABSTRACT: To investigate changes in miRNA expression in the synovial tissue, miRNA microarray was performed at day 14 after ACLT and revealed that several miRNA expressions were changed more than 1.5-fold. We chose to analyze the role of miR-21 in joint pain after ACLT because it had the highest signal intensity among the increased miRNAs. Quantitative PCR confirmed that miR-21 expression in synovial tissue was significantly increased 14 days after ACLT.
Project description:This study aimed to investigate the molecular pathways involved in muscle wasting in an animal model of osteoarthritis (OA) induced by anterior cruciate ligament transection (ACLT) in rats. Reduction of protein syntheses, increased proteolysis and impaired muscle regeneration are important pathways related to muscle wasting, and myogenin, MyoD, myostatin and MuRF-1 are some of their markers. Female Wistar rats were allocated into two groups: OA (submitted to the ACLT) and SHAM (submitted to surgery without ACLT). Nociception, spontaneous exploratory locomotion and body weight of animals were evaluated weekly. Twelve weeks after the disease induction, animals were euthanized, and the right knee joints were collected. Gastrocnemius muscle of the right hind paw were dissected and weighed. Gastrocnemius was used for evaluation of muscle atrophy and expression of IL-1?, TNF-?, Pax7, myogenin, MyoD, myostatin and MuRF-1. Histopathology of the knee confirmed the development of the disease in animals of OA group. Gastrocnemius of OA animals showed a reduction of about 10% in area and an increased IL-1? expression compared to animals of SHAM group. Expression of myostatin was increased in OA group, while myogenin expression was decreased. TNF-?, Pax7, MuRF-1 and MyoD expression was similar in both OA and SHAM groups. Nociception was significantly elevated in OA animals in the last two weeks of experimental period. Spontaneous exploratory locomotion, body weight and weight of gastrocnemius showed no difference between OA and SHAM groups. Gastrocnemius atrophy in OA induced by ACLT involves elevated expression of IL-1? within the muscle, as well as increased expression of myostatin and decreased expression of myogenin. Therefore, muscle wasting may be linked to impaired muscle regeneration.
Project description:Despite ample evidence demonstrating that anterior cruciate ligament (ACL) and meniscus tears are associated with the development of knee osteoarthritis (OA), the contributing factors remain unknown. Synovial inflammation has recently been recognized as a pivotal factor in the pathogenesis of OA. However, there is a lack of data on synovial profiles after ACL or meniscus injuries, which may contribute to posttraumatic OA (PTOA). We performed RNA-seq of 3 inflamed synovial biopsy samples vs 3 normal synovial biopsy samples following ACL and/or meniscus injuries. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and protein–protein interaction (PPI) analyses were performed to investigate mRNAs with significant differences between the inflamed and normal groups.Next, competing endogenous RNA (ceRNA) networks were constructed based on bioinformatics analyses and quantitative real-time polymerase chain reaction (RT–PCR) results. The association of the identified DEGs with the levels of infiltrating immune cells was explored using Pearson correlation analysis in R software. We aimed to provide greater insights into molecular mechanisms and biologic pathways in synovitis that could regulate post-trauma osteoarthritis progression.
Project description:Identification of novel synovial fluid biomarkers that can differentiate early changes following ACL injury from OA using tandem-mass-spectrometry
Project description:The residence time of hyaluronan (HA) in knee joint synovial fluid (SF) was investigated using a rabbit anterior cruciate ligament transection (ACLT) model. The aims of this study were to assess, at 7 and 28 days after surgery, the 1) HA concentration and molecular mass (M(r) ) distribution in the SF, 2) endogenous replenishment of HA after saline washout, 3) HA residence times in the SF, and 4) synovium and subsynovium cellularity of the knee joints of rabbits subjected to ACLT, compared to sham-operated and nonoperated control joints.Adult NZW rabbits underwent ACLT or sham surgery on one hind limb, while each contralateral limb was the nonoperated control. On day 7 or 28 after surgery, the joints were aspirated for SF, lavaged with saline, and injected with saline or polydisperse HA, and samples were obtained for analysis at set time points up to 8 hours after injection. Joint fluid samples were analyzed for the concentration and M(r) distribution of HA to calculate the HA residence time constant.Analysis of HA concentrations and M(r) distributions showed 1) loss of high-M(r) HA in the SF on day 7 and a shift toward a lower-M(r) distribution on day 28, 2) endogenous replenishment of high-M(r) HA after washout, and 3) M(r) -dependent loss of HA from the knee joints after ACLT, particularly on day 7 postsurgery. The HA residence time decreased with decreasing HA M(r) (residence time ?27 hours with an M(r) load of 7,000-2,500 kd, to ?7 hours with an M(r) load of 250-50 kd). HA residence time also decreased (by ?70%) in the knee joints on day 7 after ACLT. The subsynovium of the joints subjected to ACLT displayed increased cellularity and neovascularization on days 7 and 28 postsurgery.The residence time of HA in the SF is transiently decreased after ACLT, suggesting that a biophysical transport mechanism is responsible for the altered composition of the SF after joint injury or during inflammation.
Project description:Anterior cruciate ligament (ACL) reconstruction with preservation of either the remnant or the tibial stump is performed with the hope of improving the vascularization and proprioceptive function of the graft. Remnant preservation is technically difficult because it hinders the visualization of the intra-articular tunnel site. Taking a cue from the concept of tibial stump preservation, we have modified our ACL reconstruction technique to preserve a sleeve of the soft tissue and ACL stump attached to the femoral condyle, in addition to tibial stump preservation, while still allowing adequate visualization of the femoral ACL insertion site. We describe our modification in this article and hypothesize that this should further improve graft vascularization and ligamentization.
Project description:Knee arthroscopy has allowed us to continue performing surgeries that are minimally invasive and allow patients to have a quick recovery. Multiligamentous knee reconstruction with regards to the anterior cruciate ligament and posterior cruciate ligament can be done in a minimally invasive matter. Visualization is an issue during this surgery, especially looking in the posterior compartment of the knee. The NanoScope (Arthrex, Naples, FL) continues to provide increased possibilities for orthopaedic surgeons. Our technique provides a less-invasive way to observe the posterior compartment to assist the drilling of the tibial tunnel during the posterior cruciate ligament reconstruction. This technique provides distinct advantages over other treatments.
Project description:Osteoarthritis (OA) is a common type of arthritis characterized by degeneration of the articular cartilage and joint dysfunction. Various pharmacological and non-pharmacological techniques have been used to manage these diseases. Due to the diverse therapeutic properties of marine collagen, it has received considerable attention in its pharmacological application. Thus, the purpose of this study was to compare the efficacy of jellyfish collagen, collagen peptide, other sources of marine collagen, and glycine in treating OA. In the OA rat model, an anterior cruciate ligament transection combined with medial meniscectomy surgery (ACLT + MMx) was used to induce osteoarthritis in rats. Two weeks before surgery, male Sprague-Dawley rats were fed a chow-fat diet. After 6 weeks of treatment with collagen, collagen peptide, and glycine, the results show that they could inhibit the production of proinflammatory cytokines and their derivatives, such as COX-2, MMP-13, and CTX-II levels; therefore, it can attenuate cartilage degradation. Moreover, collagen peptides can promote the synthesis of collagen type II in cartilage. These results demonstrate that collagen and glycine have been shown to have protective properties against OA cartilage degradation. In contrast, collagen peptides have been shown to show cartilage regeneration but less protective properties. Jellyfish collagen peptide at a dose of 5 mg/kg b. w. has the most significant potential for treating OA because it protects and regenerates cartilage in the knee.
Project description:The bone-tendon-bone (BTB) autograft is widely used for anterior cruciate ligament (ACL) reconstruction. However, the primary disadvantages of this technique include postoperative kneeling pain, the risk of perioperative patellar fracture, and graft-tunnel mismatch. Therefore, a single bone plug technique for ACL reconstructions was developed to mitigate the disadvantages of the BTB technique. To differentiate this graft, we have coined the term BTA, for bone-tendon-autograft. The middle third of the patellar tendon is used with a typical width of 10 to 11 mm. A standard tibial tubercle bone plug is harvested. The length of the patellar tendon and graft construct is then measured. If the tendon is >45 mm and the construct at least 70 mm, then we proceed with the BTA technique. At the inferior pole of the patella, electrocautery is used to harvest the tendon from the patella. The advantages of this technique include faster graft harvest and preparation. Obviating the patellar bone plug harvest should eliminate the risk of perioperative patellar fracture and theoretically will mitigate donor site morbidity and kneeling pain, 2 of the most commonly cited complications of the use of BTB autografts for ACL reconstruction. In conclusion, the BTA technique is a reliable technique for ACL reconstruction.
Project description:Osteoarthritis (OA) in humans is associated with low circulating 25-hydroxyvitamin D3 [25(OH)D3]. In vitamin D replete rats, radiolabeled 24R,25-dihydroxyvitamin D3 [24R,25(OH)2D3] accumulates in articular cartilage following injection of [3H]-25(OH)D3. Previously, we showed that 24R,25(OH)2D3 blocks chondrocyte apoptosis via phospholipase D and p53, suggesting a role for 24R,25(OH)2D3 in maintaining cartilage health. We examined the ability of 24R,25(OH)2D3 to prevent degenerative changes in articular cartilage in an OA-like environment and the potential mechanisms involved. In vitro, rat articular chondrocytes were treated with IL-1β with and without 24R,25(OH)2D3 or 1α,25(OH)2D3. 24R,25(OH)2D3 but not 1α,25(OH)2D3 blocked the effects of IL-1β in a dose-dependent manner, and its effect was partially mediated through the TGF-β1 signaling pathway. In vivo, unilateral anterior cruciate ligament transections were performed in immunocompetent rats followed by intra-articular injections of 24R,25(OH)2D3 or vehicle (t = 0, 7, 14, 21 days). Tissues were harvested on day 28. Joints treated with vehicle had changes typical of OA whereas joints treated with 24R,25(OH)2D3 had less articular cartilage damage and levels of inflammatory mediators. These results indicate that 24R,25(OH)2D3 protects against OA, and suggest that it may be a therapeutic approach for preventing trauma-induced osteoarthritis.