Ligament Transection Research Articles

How I do it: The microsurgical clipping of the giant paraclinoid aneurysm using the retrograde suction decompression technique.

Paraclinoid aneurysms account for 5.4% of all intracranial aneurysms. Giant aneurysms are found in 49% of these cases. The 5-year cumulative rupture risk is 40%. Microsurgical treatment of paraclinoid aneurysms is a complex challenge that requires a personalized approach. Extradural anterior clinoidectomy and optic canal unroofing were performed in addition to orbitopterional craniotomy. Falciform ligament and distal dural ring transection provided the internal carotid artery and optic nerve mobilization. Retrograde suction decompression was used to soften the aneurysm. Clip reconstruction was performed using tandem angled fenestration and parallel clipping techniques. Orbitopterional approach with extradural anterior clinoidectomy combined with retrograde suction decompression technique is a safe and effective modality for treatment of giant paraclinoid aneurysms.

Indocyanine Green–Assisted Retrograde Ureterolysis in Robotic Transvaginal NOTES for the Management of Stage IV Endometriosis with Obliterated Cul-de-sac

To explore the use of indocyanine green (ICG) in highlighting ureteral anatomical landmarks for the successful and safe execution of robotic-assisted transvaginal NOTES hysterectomy with resection of deeply infiltrated endometriosis. Stepwise demonstration with narrated video footage. An academic tertiary care hospital. Our patient is a 38-year-old G4P1031 with a symptomatic enlarged uterus secondary to adenomyosis and uterine myomas, dense adhesions between the posterior uterus, and left uterosacral ligament. Stage IV endometriosis with obliterated cul-de-sac is a challenging procedure in the surgical management of endometriosis. Ureterolysis is the key step to performing this surgery successfully and safely; however, the routine dissection of ureters from the sacral promontory level to the uterine artery is challenging in obliterated cul-de-sacs with pelvic side wall adhesions with the proximal ureter at greatest risk [1-4]. Using the ICG firefly technique allowed us to rapidly identify and safely dissect the ureter through robotic transabdominal endometriosis surgery [5,6]. The angle of approach in transvaginal NOTES surgery for hysterectomy with obliterated cul-de-sac endometriosis leads to far more difficulty in identifying the ureter at the beginning of surgery [3]. Therefore, an obliterated cul-de-sac was associated with a potentially increased risk of ureteral injury and bowel injury. We used ICG to help identify the ureter at the beginning of the case leading to reducing the risk of surgical complication, in which the concept of ureterolysis from the level of the uterine artery to the bifurcation of common iliac vessels in vNOTES surgery will be referred to as "vNOTES retrograde ureterolysis." With the cystoscope in place, a ureteral catheter was inserted into the right ureter and 5 cc of ICG was injected, and the same procedure was done on the left [1,5]. Bovie electrosurgical device was used to incise circumferentially around the cervix. The bladder was dissected off the pubovesical cervical fascia anteriorly and posteriorly with a combination of the Bovie as well as blunt and sharp dissection. Bilateral uterosacral and cardinal ligaments, as well as uterine arteries, were then clamped, transected with Mayo scissors, and secured. Entry into the anterior cul-de-sac was completed, and a stitch using 0 vicryl was used to tag the anterior peritoneum to the anterior vaginal cuff.Posterior entry was attempted unsuccessfully. The Gelpoint mini device was then placed, and the Da Vinci XI robot was docked. Bilateral ureters were identified and dissected out of bilateral pelvic sidewalls using the firefly mode at the level of the uterine artery. The ureters were easily dissected away from the uterus. The left broad ligament was then cauterized and transected using the vessel sealer. The plane between the uterus and the rectum was identified laterally, and the rectum was taken down from the uterus from the right to the left side.Bilateral broad ligaments were then cauterized and transected using the vessel sealer, followed by cauterization and transection of the round ligaments, utero-ovarian ligaments, and mesosalpinx bilaterally. The vaginal cuff angles were secured with a figure-of-eight stitch of 0 vicryl, and the vaginal cuff was then closed in a running fashion with 0 V-Loc.The patient was discharged in one day with reports of minimal pain (Videos 1-3). Robotic-assisted NOTES hysterectomy with deeply infiltrated endometriosis resection is feasible and safe with ICG-assisted ureteral labeling in a case of obliterated cul-de-sac. The unique green color labeling of ureters offers a prominent landmark in assisting the ureteral dissection while avoiding ureteral and bowel injury, resulting in the possibility of using vNOTES surgery in challenging cases.

Ex vivo evaluation of arthroscopically assisted shoulder stabilization in dogs using an intra-articular aiming device.

To evaluate the use of an intra-articular aiming device (IAD) for medial shoulder stabilization with a suture-toggle repair or an interference screw repair using bone anchors in dogs. Ex-vivo Study METHODS: Specimens were randomly divided into 2 groups (anchor and suture-toggle) with 10 shoulders each. Abduction angles were measured by goniometry prior to and following medial glenerohumeral ligament transection and after receiving arthroscopically assisted stabilization with either bone anchors or suture-toggle constructs. Bone stock and insertion angles were measured with computed tomography scans. All specimens were inspected by dissection. Abduction angles increased post-transection in both groups, and were restored to normal in the anchor group, but 2° smaller than normal in the suture-toggle group following stabilization. Median magnitude of bone stock surrounding all tunnels ranged between 5.9 and 12.9 mm in the anchor group and 8.8 and 15.6 mm in the suture-toggle group (p=.002). Median insertion angles at the cranial glenoid, caudal glenoid, and humerus were 17.3°, 36.8 ° and 43.4° in the anchor group, respectively, and median insertion angles at the glenoid and humerus were 38.2° and 35.6° in the suture-toggle group, respectively (p=.91). Placement of anchors were not feasible in 3 specimens in the anchor group, and mild violations of the articular surfaces were detected in 3 specimens overall. Arthroscopically assisted shoulder stabilization with an IAD was feasible in canine cadavers. An IAD may facilitate arthroscopic shoulder stabilization in dogs. Further studies are warranted to evaluate safety and efficacy in a clinical setting.

Indole-3-propionic acid alleviates chondrocytes inflammation and osteoarthritis via the AhR/NF-κB axis

BackgroundOsteoarthritis (OA) is a common chronic disease characterized by chronic inflammation and extracellular matrix degradation. Indole-3-propionic acid (IPA) is a tryptophan metabolite secreted by intestinal flora, which can exert anti-inflammatory effects in a variety of diseases. In this study, we further investigated the potential therapeutic role of IPA in OA and the underlying mechanism.MethodsIL-1β was utilized to induce chondrocyte inflammation. Then, the cytotoxicity of IPA on rat chondrocytes was assessed. Meanwhile, RT-qPCR, Griess reaction, ELISA, Western blot and immunofluorescence were performed to evaluate the expression of inflammatory factors and stromal proteins, and the NF-κB pathway in chondrocytes treated with IL-1β alone, with IPA or with aryl hydrocarbon receptor (AhR) knockdown. An OA rat model was established by anterior cruciate ligament transection, and hematoxylin-eosin staining, Safranin-O/Fast Green staining and immunochemistry were applied to estimate OA severity.ResultsIPA did not affect cellular viability at concentrations up to 80 µM. IPA significantly inhibited the IL-1β-induced expression of inflammatory factors (Nitric oxide, PGE2, TNF-α, IL-6, iNOS and COX-2) and matrix-degrading enzymes (MMP-3, MMP-13 and ADAMTS-5), upregulated the expression of anabolic markers (aggrecan and collagen-II) and inactivated the NF-κB pathway. However, AhR knockdown could abolish the above protection capabilities and the suppression of the NF-κB pathway induced by IPA. Furthermore, IPA significantly reduced serum inflammatory cytokines expression, cartilage destruction and synovitis in vivo, demonstrating its protective role in OA progression.ConclusionIPA improved IL-1β-induced chondrocyte inflammation and extracellular matrix degradation through the AhR/NF-κB axis, which provides an innovative therapeutic strategy for OA.

Fermented jellyfish (Rhopilema esculentum) collagen enhances antioxidant activity and cartilage protection on surgically induced osteoarthritis in obese rats.

Collagen has been considered a key treatment option in preventing damage to the articular cartilage over time and supporting the healing process, following the onset of osteoarthritis (OA). This study aimed to investigate the effect of collagen fermented from jellyfish (FJC) by Bacillus subtilis natto on anterior cruciate ligament transection with medial meniscectomy (ACLT + MMx)-induced knee OA in high-fat diet (HFD)-induced obesity in rats. The male Sprague-Dawley rats were fed an HFD for 6weeks before ACLT + MMx surgery, after which they were administered a daily oral gavage of saline (control, OA, and OBOA), either with FJC (20mg/kg, 40mg/kg, and 100mg/kg body weight) or glucosamine sulfate as a positive control (GS; 200mg/kg body weight) for 6weeks. Treatment with FJC decreased the fat weight, triglyceride, and total cholesterol levels in obese rats. Additionally, FJC downregulated the expression of some proinflammatory cytokines, including tumor necrosis factor-α, cyclooxygenase-2, and nitric oxide; suppressed leptin and adiponectin expression; and attenuated cartilage degradation. It also decreased the activities of matrix metalloproteinase (MMP)-1 and MMP-3. These results demonstrated that FJC showed a protective effect on articular cartilage and also suppressed the degradation of cartilage in an animal OA model, suggesting its potential efficacy as a promising candidate for OA treatment.

Functional Loss of Terminal Complement Complex Protects Rabbits from Injury-Induced Osteoarthritis on Structural and Cellular Level.

The terminal complement complex (TCC) has been described as a potential driver in the pathogenesis of posttraumatic osteoarthritis (PTOA). However, sublytic TCC deposition might also play a crucial role in bone development and regeneration. Therefore, we elucidated the effects of TCC on joint-related tissues using a rabbit PTOA model. In brief, a C6-deficient rabbit breed was characterized on genetic, protein, and functional levels. Anterior cruciate ligament transection (ACLT) was performed in C6-deficient (C6-/-) and C6-sufficient (C6+/-) rabbits. After eight weeks, the progression of PTOA was determined histologically. Moreover, the structure of the subchondral bone was evaluated by µCT analysis. C6 deficiency could be attributed to a homozygous 3.6 kb deletion within the C6 gene and subsequent loss of the C5b binding site. Serum from C6-/- animals revealed no hemolytic activity. After ACLT surgery, joints of C6-/- rabbits exhibited significantly lower OA scores, including reduced cartilage damage, hypocellularity, cluster formation, and osteophyte number, as well as lower chondrocyte apoptosis rates and synovial prostaglandin E2 levels. Moreover, ACLT surgery significantly decreased the trabecular number in the subchondral bone of C6-/- rabbits. Overall, the absence of TCC protected from injury-induced OA progression but had minor effects on the micro-structure of the subchondral bone.

Achyranthoside D attenuates chondrocyte loss and inflammation in osteoarthritis via targeted regulation of Wnt3a

BackgroundAchyranthes bidentata Blume (A. bidentata) is a common Chinese herb used to treat osteoarthritis (OA). Achyranthoside D (Ach-D) is a glucuronide saponin isolated from A. bidentata. PurposeTo assess the mechanisms of action of Ach-D and its effects on OA. MethodsThe effects of Ach-D were evaluated in rats underwent anterior cruciate ligament transection (ACLT) with medial meniscectomy (MMx) and in interleukin (IL)-1β-induced chondrocytes. Histological changes in rat cartilage tissues were detected using Safranin O-Fast green and haematoxylin-eosin staining. Immunohistochemical staining, qRT-PCR, ELISA, immunoblotting, and immunofluorescence were conducted to examine cartilage degeneration-related and inflammation-related factor expression. CCK-8, LDH assay, and EdU staining were performed to detect chondrocyte death. ResultsAch-D dose-dependently reduced the Osteoarthritis Research Society International (OARSI) scores, alleviated cartilage injury, and decreased the serum concentrations of CTX-II and COMP in ACLT-MMx models. Ach-D increased the expression levels of collagen II and aggrecan and decreased the levels of cartilage degeneration-related proteins, ADAMTS-5, MMP13, and MMP3, in rat cartilage tissues. Additionally, nod-like receptor protein 3 (NLRP3)-related inflammation was reduced by Ach-D, as shown by the significantly inhibited expression levels of NLRP3, ASC, GSDMD, IL-6, TNF-α, IL-1β, and IL-18 in rat cartilage tissues. In primary rat chondrocytes, Ach-D protected against IL-1β-induced viability loss and LDH release. Wnt3a is the target protein of Ach-D. Mechanistically, Ach-D alleviated OA by inhibiting Wnt signalling. ConclusionACH-D may reduce inflammation and cartilage degeneration by inhibiting the Wnt signalling pathway, thereby reducing OA.

Therapeutic effect of induced pluripotent stem cell -derived extracellular vesicles in an in vitro and in vivo osteoarthritis model.

Osteoarthritis (OA) is a multifactorial joint disease associated with the deterioration of chondrocytes and inflammation. Treatment of OA is only aimed at reducing pain and improving joint function. Recently, extracellular vesicles (EVs) secreted from stem cells have emerged as a cell regenerative tool in several degenerative diseases, including OA. We hypothesised that induced pluripotent stem cell (iPSC)-derived EVs would be beneficial for regenerating chondrocytes and OA therapy. Therefore, we aimed to investigate iPSC-EVs' effects on chondrocyte behaviour in an interleukin 1 beta (IL-1β)-induced in vitro OA model and anterior cruciate ligament transection (ACLT)-induced in vivo OA model of rabbit articular cartilage. The iPSC-EVs were isolated by sequential ultracentrifugation from a 48-h-incubated conditional medium of iPSC. The isolated iPSC-EVs were characterised by transmission electron microscopy, western blot analyses, and dynamic light scatter. The effects of iPSC-EVs on the viability of human primary chondrocytes and cell senescence were analysed. Premature senescence of cells was induced by long-term incubation with low doses of hydrogen peroxide. To investigate the therapeutic effect of iPSC-EVs on OA chondrocytes in vitro, IL-1β was used to induce chondrocyte damage. Inflammatory macrophages were activated from THP-1 monocytes to observe the impact of iPSC-EV on macrophage polarisation. The phenotypes of the macrophages exposed to iPSC-EVs were evaluated by ELISA and western blot analyses. The primary chondrocytes were co-cultured with different phenotypes of macrophages to observe the expression of collagen II and catabolic enzymes in chondrocytes. iPSC-EVs were injected intraarticularly into the rabbit with an ACLT-induced OA model. The progression of lesions was assessed through macroscopic and histopathological studies. We showed that iPSC-EVs significantly stimulated the proliferation of primary human chondrocytes and suppressed cell senescence by regulating the expression of p21 and collagen II. iPSC-EVs reduced matrix degradation enzymes and IL-6 expression and attenuated IL-1β-mediated cell death of chondrocytes. Furthermore, iPSC-EVs modulated macrophage polarisation, resulting in the rescue of damaged chondrocytes in an inflammatory microenvironment. In the rabbit ACLT model, the OA-like lesions, including inflammation, subchondral bone protrusion, and articular cartilage destruction, were ameliorated by iPSC-EV. A histopathological study consistently revealed that iPSC-EVs attenuated ACLT-mediated alteration of MMP13 and ADAMTS5 and collagen II expression. iPSC-EVs protected chondrocytes by enhancing cell proliferation, suppressing premature senescence, and maintaining homeostasis of collagen II synthesis and matrix degradation enzymes such as matrix metalloproteinases (MMPs) and ADAMTS5. iPSC-EVs also reduced cell death in IL-1β-mediated chondrocyte cell damage. In the rabbit ACLT-induced OA model, iPSC-EV injection reduced cartilage destruction, as indicated by the upregulation of collagen II and down-regulation of MMP13 and ADAMTS5. Overall, our results suggest that iPSC-EVs possess therapeutic potential and may be used as an OA treatment option. This study highlights the potential of iPSC-EVs as a therapeutic option for chondrocyte regeneration and OA treatment.

The novel hyaluronic acid granular hydrogel attenuates osteoarthritis progression by inhibiting the TLR-2/NF-κB signaling pathway through suppressing cellular senescence.

In patients with mild osteoarthritis (OA), two to four monthly injections are required for 6months due to the degradation of hyaluronic acid (HA) by peroxidative cleavage and hyaluronidase. However, frequent injections may lead to local infection and also cause inconvenience to patients during the COVID-19 pandemic. Herein, we developed a novel HA granular hydrogel (n-HA) with improved degradation resistance. The chemical structure, injectable capability, morphology, rheological properties, biodegradability, and cytocompatibility of the n-HA were investigated. In addition, the effects of the n-HA on the senescence-associated inflammatory responses were studied via flow cytometry, cytochemical staining, Real time quantitative polymerase chain reaction (RT-qPCR), and western blot analysis. Importantly, the treatment outcome of the n-HA with one single injection relative to the commercial HA product with four consecutive injections within one treatment course in an OA mouse model underwent anterior cruciate ligament transection (ACLT) was systematically evaluated. Our developed n-HA exhibited a perfect unification of high crosslink density, good injectability, excellent resistance to enzymatic hydrolysis, satisfactory biocompatibility, and anti-inflammatory responses through a series of in vitro studies. Compared to the commercial HA product with four consecutive injections, a single injection of n-HA contributed to equivalent treatment outcomes in an OA mouse model in terms of histological analysis, radiographic, immunohistological, and molecular analysis results. Furthermore, the amelioration effect of the n-HA on OA development was partially ascribed to the attenuation of chondrocyte senescence, thereby leading to inhibition of TLR-2 expression and then blockade of NF-κB activation. Collectively, the n-HA may be a promising therapeutic alternative to current commercial HA products for OA treatment.

Mouse model of subtalar post-traumatic osteoarthritis caused by subtalar joint instability

BackgroundCommon ankle sprains are often accompanied by injury to the subtalar joint, which eventually leads to subtalar joint instability. Because the clinical manifestations for subtalar joint instability are similar to ankle joint injuries, these are often overlooked. This study aimed to establish an animal model of subtalar joint instability to study post-traumatic osteoarthritis of the subtalar joint caused by long-term subtalar joint instability and to provide a reference for future clinical research on chronic subtalar joint instability.MethodsIn all, 24 C57BL/6 male mice were randomly divided into three groups: Sham, cervical ligament (CL) transection and CL + calcaneofibular ligament (CFL) transection groups. One week after surgical operation, all mice were trained to run in the mouse rotation fatigue machine every day. During this period, a balance beam test was used to evaluate the motor level and coordination ability of the mice before the operation and three days, one week, four weeks, eight weeks, and twelve weeks after operation. Further, post-traumatic osteoarthritis of the subtalar joint was quantified via micro-CT and histological staining.ResultsThe mice in the partial ligament transection group took significantly longer than those in the Sham group to pass through the balance beam and showed an increased number of hindfoot slips. Micro-CT analysis showed that the subtalar bone volume fraction in the CL + CFL transection group and CL transection group was 5.8% and 2.8% higher than that in the Sham group, respectively. Histological staining showed obvious signs of post-traumatic osteoarthritis (PTOA) in the subtalar joint of the ligament transection group.ConclusionsThe transection of CL and CL + CFL can cause instability of the subtalar joint in mice, resulting in a decrease in motor coordination, and long-term instability of the subtalar joint in mice can cause PTOA of the subtalar joint, which is manifested as destruction and loss of articular cartilage.

Gardenoside ameliorates inflammation and inhibits ECM degradation in IL-1β-treated rat chondrocytes via suppressing NF-κB signaling pathways

Osteoarthritis (OA) places a significant burden on society and finance, and there is presently no effective treatment beside late replacement surgery and symptomatic relief. The therapy of OA requires additional research. Gardenoside is a naturally compound extracted from Gardenia jasminoides Ellis, which has a variety of anti-inflammatory effects. However, few studies have been conducted to determine the role of gardenoside in OA. This study aimed to explore whether gardenoside has effect in OA treatment. Rat primary chondrocytes were treated with IL-1β to simulate inflammatory environmental conditions and OA in vitro. We examined the effects of gardenoside at concentrations ranging from 0 to 200 μM on the viability of rat chondrocytes and selected 10 μM for further study. Via in vitro experiments, our study found that gardenoside lowers the gene expression of COX-2, iNOS, IL-6, and reduced the ROS production of chondrocytes induced by IL-1β. Moreover, it effectively alleviates ECM degradation caused by IL-1β and promotes the ECM synthesis in chondrocytes by upregulating collagen-II and the ACAN expression, downregulating the expression of MMP-3, MMP-13, and ADAMTS-5 expression. Further, our study showed that gardenoside inhibits NF-κB signaling pathway activated by IL-1β in chondrocytes. We established an OA rat model by anterior cruciate ligament transection (ACLT). The animals were then periodically injected with gardenoside into the knee articular cavity. In vivo study suggested that gardenoside attenuates OA progression in rats. As a whole, in vitro and in vivo results highlight gardenoside is a promising OA treatment agent.

Blockade of JAK2 retards cartilage degeneration and IL-6-induced pain amplification in osteoarthritis.

Osteoarthritis (OA) is a complex chronic inflammatory disease characterized by articular degeneration and pain. Recent studies have identified interleukin 6 (IL-6) as a potential mediator leading to OA, but the therapeutic effects of inhibiting IL-6 signaling in intreating OA need to be further clarified. Here, we identified the intracellular signal transduction induced by recombinant IL-6 and focused on the impact of tyrphostin AG490 (a JAK2 inhibitor) on cartilage degeneration and OA pain. We found that IL-6 increased the inflammatory cytokines production and hypertrophic markers expression of primary mouse chondrocytes by activating JAK2/STAT3. Meanwhile, tyrphostin AG490 significantly attenuated articular degeneration and osteophyte formation in experimental mice with anterior cruciate ligament transection (ACLT) surgery. In vivo electrophysiological experiments showed that articular stimulation of IL-6 induced spinal hyperexcitability, which was prevented by coinjection of tyrphostin AG490. Specifically, compared with DMSO-treated ACLT mice, tyrphostin AG490 improved ambulate activity of mice and abolished the enhancement of serum bradykinin induced by IL-6. Together, we suggest that tyrphostin AG490 protected against progression of OA and improved OA prognosis by reducing cartilage degeneration and arthritis pain. Our findings provide further evidence for targeting IL-6 signaling in the treatment of OA.

Intra-articular injection of placental mesenchymal stromal cells ameliorates pain and cartilage anabolism/catabolism in knee osteoarthritis.

Background: Knee Osteoarthritis (kOA), the most common joint degenerative disorder, lacks effective therapeutics. Placenta-derived mesenchymal stromal cells (PMSCs) are effective in tissue repairing and generation, which have potential in treating kOA. This study aimed to determine the anti-kOA efficacy of PMSCs and to explore its action mode. Methods: Flow cytometry and three-line differentiation were performed for identification of PMSCs. In vivo, a rat kOA model established by anterior cruciate ligament transection (ACLT) surgery was used to evaluate the efficacy of PMSCs. Histopathological HE and SO staining with Osteoarthritis Research Society International scoring were conducted, and cartilage expressions of MMP13 and Col2 were measured by immunohistochemistry. Pain behavior parameters by mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL), were measured. In vitro, wound healing and cell immunofluorescence assays were conducted to detect the proliferation and migration ability of chondrocytes treated with PMSCs conditioned medium (PMSCs-CM). Quantitative real-time PCR (qRT-PCR) and Western blot (WB) assays were applied to explore the molecular action of PMSCs on chondrocytes. Results: The results of flow cytometry indicated that the surface markers of PMSCs (CD73 > 95%, CD90 > 95%, and CD34 < 2%) were consistent with the typical mesenchymal stromal cells. The in vivo data showed that PMSCs significantly reversed the kOA progression by protection of cartilage, regulation of anabolic (Col2) and catabolic (MMP13) expressions, and relief of pain symptoms. The in vitro data showed that PMSCs promoted chondrocyte proliferation and migration and significantly restored the IL-1β-induced abnormal gene expressions of Col2, Mmp13, Adamts4, Adamts5 and Sox9 and also restored the abnormal protein expressions of Col2, Mmp13 and Sox9 of chondrocytes. The molecular actions of PMSCs on chondrocytes in nested co-culture way or in conditioned medium way were similar, confirming a paracrine-based mode of action. Conclusion: This study demonstrated PMSCs' anti-kOA efficacy and its paracrine-based action mode, providing novel knowledge of PMSCs and suggesting it as a promising cell therapy for treatment of kOA.

Cholesterol-induced LRP3 downregulation promotes cartilage degeneration in osteoarthritis by targeting Syndecan-4

Emerging evidence suggests that osteoarthritis is associated with high cholesterol levels in some osteoarthritis patients. However, the specific mechanism under this metabolic osteoarthritis phenotype remains unclear. We find that cholesterol metabolism-related gene, LRP3 (low-density lipoprotein receptor-related protein 3) is significantly reduced in high-cholesterol diet mouse’s cartilage. By using Lrp3−/− mice in vivo and LRP3 lentiviral-transduced chondrocytes in vitro, we identify that LRP3 positively regulate chondrocyte extracellular matrix metabolism, and its deficiency aggravate the degeneration of cartilage. Regardless of diet, LRP3 overexpression in cartilage attenuate anterior cruciate ligament transection induced osteoarthritis progression in rats and Lrp3 knockout-induced osteoarthritis progression in mice. LRP3 knockdown upregulate syndecan-4 by activating the Ras signaling pathway. We identify syndecan-4 as a downstream molecular target of LRP3 in osteoarthritis pathogenesis. These findings suggest that cholesterol-LRP3- syndecan-4 axis plays critical roles in osteoarthritis development, and LRP3 gene therapy may provide a therapeutic regimen for osteoarthritis treatment.

High-dose Tiger-Gian formula protects the knee joint from surgically induced osteoarthritis in rats.

Although the Tiger-Gian formula (TGF) has proven clinically effective at improving the symptoms of knee osteoarthritis (KOA), the pharmacological effects and underlying mechanisms of TGF have not been examined in any animal model. This study assessed the effects of TGF in male Sprague-Dawley rats with anterior cruciate ligament transection (ACLT) -induced KOA. Thirty rats underwent ACLT surgery and were assigned to either the control group, ACLT alone, ACLT + low-dose TGF (1000 mg/kg), ACLT + high-dose TGF (3000 mg/kg), or ACLT + celecoxib (30 mg/kg). All rats were subjected to micro-computed tomography (micro-CT), weight-bearing behavioral testing, and histological inspections of the knee joint for evidence of structural changes in articular bone, cartilage and synovium. After 6 weeks, force discrepancies in weight-bearing distribution between the normal hind and postoperative limbs revealed superiority with high-dose TGF (18.00 ± 5.93 g) and celecoxib (18.68 ± 5.29 g) versus both ACLT alone (41.29 ± 7.06 g) and low-dose TGF (37.00 ± 7.40 g). Micro-CT images revealed that high-dose TGF and celecoxib similarly improved subchondral bone architecture, protected articular cartilage after ACLT, and downregulated proinflammatory cytokines interleukin-1β and tumor necrosis factor-α in the cartilage and synovial sections. High-dose TGF induced the smallest amount of KOA-associated bone loss. Anti-inflammatory, anti-oxidative, and immunomodulatory effects of TGF were accompanied by reductions in proinflammatory cytokines and improvements in pain and function. TGF-induced anti-osteoporotic activity and inhibition of cartilage degradation were reflected by micro-CT and histological analysis. The findings help to explain how TGF alleviates symptoms of KOA.

Development of a cyclic-inverso AHSG/Fetuin A-based peptide for inhibition of calcification in osteoarthritis

Ectopic calcification is an important contributor to chronic diseases, such as osteoarthritis. Currently, no effective therapies exist to counteract calcification. We developed peptides derived from the calcium binding domain of human Alpha-2-HS-Glycoprotein (AHSG/Fetuin A) to counteract calcification. A library of seven 30 amino acid (AA) long peptides, spanning the 118 AA Cystatin 1 domain of AHSG, were synthesized and evaluated in an in vitro calcium phosphate precipitation assay. The best performing peptide was modified (cyclic, retro-inverso and combinations thereof) and evaluated in cellular calcification models and the rat Medial Collateral Ligament Transection + Medial Meniscal Tear (MCLT+MMT) osteoarthritis model. A cyclic peptide spanning AA 1-30 of mature AHSG showed clear inhibition of calcium phosphate precipitation in the nM-pM range that far exceeded the biological activity of the linear peptide variant or bovine Fetuin. Biochemical and electron microscopy analyses of calcium phosphate particles revealed a similar, but distinct, mode of action in comparison with bFetuin. A cyclic-inverso variant of the AHSG 1-30 peptide inhibited calcification of human articular chondrocytes, vascular smooth muscle cells and during osteogenic differentiation of bone marrow derived stromal cells. Lastly, we evaluated the effect of intra-articular injection of the cyclic-inverso AHSG 1-30 peptide in a rat osteoarthritis model. A significant improvement was found in histopathological osteoarthritis score and animal mobility. Serum levels of IFNγ were found to be lower in AHSG 1-30 peptide treated animals. The cyclic-inverso AHSG 1-30 peptide directly inhibits the calcification process and holds the potential for future application in osteoarthritis.

Antioxidant PDA-PEG nanoparticles alleviate early osteoarthritis by inhibiting osteoclastogenesis and angiogenesis in subchondral bone

Accumulating evidence suggests that osteoclastogenesis and angiogenesis in subchondral bone are critical destructive factors in the initiation and progression of osteoarthritis (OA). Herein, methoxypolyethylene glycol amine (mPEG-NH2) modified polydopamine nanoparticles (PDA-PEG NPs) were synthesized for treating early OA. The cytotoxicity and reactive oxygen species (ROS) scavenging ability of PDA-PEG NPs were evaluated. The effects of PDA-PEG NPs on osteoclast differentiation and vessel formation were then evaluated. Further, PDA-PEG NPs were administrated to anterior cruciate ligament transection (ACLT)-induced OA mice. Results demonstrated that PDA-PEG NPs had low toxicity both in vitro and in vivo. PDA-PEG NPs could inhibit osteoclastogenesis via regulating nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Moreover, PDA-PEG NPs suppressed osteoclast-related angiogenesis via down-regulating platelet-derived growth factor-BB (PDGF-BB). In vivo, PDA-PEG NPs inhibited subchondral bone resorption and angiogenesis, further rescuing cartilage degradation in OA mice. In conclusion, we demonstrated that PDA-PEG NPs deployment could be a potential therapy for OA.Graphical

The Effect of Different Frequencies of Pulsed Electromagnetic Fields on Cartilage Repair of Adipose Mesenchymal Stem Cell-Derived Exosomes in Osteoarthritis.

The intra-articular injection of mesenchymal stem cell (MSC)-derived exosomes has already been proved to reverse osteoarthritic cartilage degeneration. Pulsed electromagnetic field (PEMF) has been found to regulate the biogenic function of MSCs. However, the effect of PEMF on MSC-derived exosomes has not yet been characterized. The aim of this study was to elucidate the regulatory role of different frequencies of PEMF in promoting the osteoarthritic cartilage regeneration of MSC-derived exosomes. The adipose tissue-derived MSCs (AMSCs) were extracted from the epididymal fat of healthy rats and further exposed to the PEMF at 1 mT amplitude and a frequency of 15, 45, and 75 Hz, respectively, in an incubator. The chondrocytes were treated with interlukin-1β (IL-1β) and the regenerative effect of co-culturing with PEMF-exposed AMSC-derived exosomes was assessed via Western blot, quantitative polymerase chain reaction, and ELISA assays. A rat model of osteoarthritis was established by anterior cruciate ligament transection (ACLT) surgery and received 4 times intra-articular injection of PEMF-exposed AMSC-derived exosomes once a week. After 8 weeks, the knee joint specimens of rats were collected for micro-computed tomography and histologic analyses. PEMF-exposed AMSC-derived exosomes could be endocytosed with IL-1β-induced chondrocytes. Compared with the AMSC-derived exosomes alone, the PEMF-exposed AMSC-derived exosomes substantially suppressed the inflammation and extracellular matrix degeneration of IL-1β-induced chondrocytes as shown by higher expression of transcripts and proteins of COL2A1, SOX9, and ACAN and lower expression of MMP13 and caspase-1. Of these, the 75-Hz PEMF presented a more significant inhibitive effect than the 15-Hz and 45-Hz PEMFs. Furthermore, the intra-articular injection of 75-Hz PEMF-exposed exosomes could obviously increase the number of tibial epiphyseal trabeculae, lead to a remarkable decrease in Osteoarthritis Research Society International score, and upregulate the COL2A1 and ACAN protein level of the degenerated cartilage. The present study demonstrated that PEMF stimulation could effectively promote the regeneration effects of AMSC-derived exosomes on osteoarthritic cartilage. Compared with other frequency parameters, the PEMF at a frequency of 75 Hz showed a superior positive effect on AMSC-derived exosomes in suppressing the IL-1β-induced chondrocyte inflammation and extracellular matrix catabolism, as well as the osteoarthritic cartilage degeneration.

Quantitative evaluation of very early cartilage damage in experimental osteoarthritis using scanning electron microscopy

ObjectiveTo describe parametric changes observed using scanning electron microscopy (SEM) in very early stages in posttraumatic osteoarthritis (OA) models in mice.MethodsMice (5/group) had their knees subjected to anterior cruciate ligament transection (ACLT), ACLT plus meniscectomy (MNCT) or sham surgery, sacrificed after 3, 7 or 14 days, had the articular cartilage evaluated under optical microscopy using Osteoarthritis Research Society International (OARSI) parameters as well as cartilage thickness, roughness, and a damage index using SEM.ResultsAlterations of the cartilage under optical microscopy were not significantly relevant among groups. SEM analysis revealed reduction of femoral and tibial cartilage thickness in ACLT and MNCT groups at 7 and 14 days, with increased cartilage roughness in MNCT group as early as 3 days postsurgery, being sustained up to 14 days. Articular damage index was significantly higher at 14 days post surgery in ACLT and MNCT vs control groups.ConclusionThis is the first demonstration of very early quantitative changes in the cartilage of mice subjected to posttraumatic experimental OA using SEM, revealing increased roughness and thickness as early as 3 days post surgery. These changes may be used as early surrogates for later joint damage in experimental OA.

Stress radiographic assessment of collateral ligament constraints on the feline tarsocrural joint.

This cadaveric study describes the collateral ligament constraints on the feline tarsocrural joint using stress radiography. Thirty-six feline cadaveric hindlimbs free of orthopaedic disease were placed in a custom-made jig and controlled stress radiography was performed before and after transection of one, or both collateral ligaments. Changes in varus and valgus deviation and pronation and supination were measured at three limb angles (extension, 120o flexion and 90o flexion). There was a significant positive percentage change in the mean angle of varus deviation after transection of the fibulocalcaneal ligament at all limb positions (extension: 41%, 120°: 78%, 90°: 63%). There was a significant positive percentage change in the mean angle of varus deviation after transection of the fibulotalar ligament at extension (14%). There was a significant positive percentage change in the mean angle of varus deviation after transection of both fibulocalcaneal and fibulotalar ligaments at all limb positions (extension: 58%, 120°: 67%, 90°: 67%), and in the mean angle of valgus deviation (100%) and supination (89%) at 90 degrees flexion. There was a significant positive percentage change in the mean angle of valgus deviation after transection of the tibiocentral ligament at all limb positions (extension: mean 79%, 120°: 43%, 90°: 49%) and the mean angle of pronation at 120 degrees flexion (10%). There was a significant positive percentage change in the mean angle of varus deviation after transection of the tibiotalar ligament at extension (11%) and at 90 degrees flexion (54%) and in the mean angle of pronation at all limb positions (extension: 11%, 120°: 19%, 90°: 32%). There was a significant positive percentage change in the mean angle of valgus deviation (extension: 255%, 120°: 172%, 90°: 176%) and pronation (extension: 58%, 120°: 134%, 90°: 76%) after transection of the tibiocentral and tibiotalar ligaments at all limb positions and in the mean angle of varus deviation at extension (13%) and 90 degrees flexion (69%). The medial collateral ligaments prevent against excessive valgus deviation and pronation, and the lateral collateral ligaments prevent against excessive varus deviation and supination. At 90 degrees flexion subluxation of the talus occurs on the ipsilateral side of the ligament injury resulting in an additional direction of instability.