Efficacy of intra-articular injection of celecoxib in a rabbit model of osteoarthritis

Sustained release of locally delivered celecoxib provides pain relief for osteoarthritis: a proof of concept in dog patients

OBJECTIVE

Drug delivery platforms that allow for gradual drug release after intra-articular administration have become of much interest as a treatment strategy for osteoarthritis (OA). The aim of this study was to investigate the safety and efficacy of an intra-articular sustained release formulation containing celecoxib (CXB), a cyclooxygenase-2 (COX-2) selective inhibitor.

METHODS

Amino acid-based polyesteramide microspheres (PEAMs), a biodegradable and non-toxic platform, were loaded with CXB and employed in two in vivo models of arthritis: an acute inflammatory arthritis model in rats (n = 12), and a randomized controlled study in chronic OA dog patients (n = 30). In parallel, the bioactivity of sustained release of CXB was evaluated in monolayer cultures of primary dog chondrocytes under inflammatory conditions.

RESULTS

Sustained release of CXB did not alleviate acute arthritis signs in the rat arthritis model, based on pain measurements and synovitis severity. However, in OA dog patients, sustained release of CXB improved limb function as objective parameter of pain and quality of life based on gait analysis and owner questionnaires. It also decreased pain medication dependency over a 2-month period and caused no adverse effects. Prostaglandin E2 levels, a marker for inflammation, were lower in the synovial fluid of CXB-treated dog OA patients and in CXB-treated cultured dog chondrocytes.

CONCLUSION

These results show that local sustained release of CXB is less suitable to treat acute inflammation in arthritic joints, while safe and effective in treating pain in chronic OA in dogs.

Evaluation of the Anti-Inflammatory and Chondroprotective Effect of Celecoxib on Cartilage Ex Vivo and in a Rat Osteoarthritis Model

OBJECTIVE

The potential chondroprotective effect of celecoxib, a nonsteroidal anti-inflammatory drug and selective cyclooxygenase-2 inhibitor used to reduce pain and inflammation in knee osteoarthritis patients, is disputed. This study aimed at investigating the chondroprotective effects of celecoxib on (1) human articular cartilage explants and (2) in an in vivo osteoarthritis rat model.

DESIGN

Articular cartilage explants from 16 osteoarthritis patients were cultured for 24 hours with celecoxib or vehicle. Secreted prostaglandins (prostaglandin E₂, prostaglandin F_2α, prostaglandin D₂) and thromboxane B2 (TXB2) concentrations were determined in medium by ELISA, and protein regulation was measured with label-free proteomics. Cartilage samples from 7 of these patients were analyzed for gene expression using real-time quantitative polymerase chain reaction. To investigate the chondroprotective effect of celecoxib in vivo, 14 rats received an intra-articular injection of celecoxib or 0.9% NaCl after osteoarthritis induction by anterior cruciate ligament transection and partial medial meniscectomy (ACLT/pMMx model). Histopathological scoring was used to evaluate osteoarthritis severity 12 weeks after injection.

RESULTS

Secretion of prostaglandins, target of Nesh-SH3 (ABI3BP), and osteonectin proteins decreased, whereas tissue inhibitor of metalloproteinase 2 (TIMP-2) increased significantly after celecoxib treatment in the human (ex vivo) explant culture. Gene expression of a disintegrin and metalloproteinase with thrombospondin motifs 4 and 5 (ADAMTS4/5) and metalloproteinase 13 (MMP13) was significantly reduced after celecoxib treatment in human cartilage explants. Cartilage degeneration was reduced significantly in an in vivo osteoarthritis knee rat model.

CONCLUSIONS

Our data demonstrated that celecoxib acts chondroprotective on cartilage ex vivo and a single intra-articular bolus injection has a chondroprotective effect in vivo.

Pharmacokinetics, safety and efficacy of intra-articular non-steroidal anti-inflammatory drug injections for the treatment of osteoarthritis: A narrative review

What is known and Objective

Osteoarthritis (OA) is a common cause of joint disease and activity limitation in adults. Common therapies to treat OA‐related pain are oral and topical non‐steroidal anti‐inflammatory drugs (NSAIDs) and intra‐articular (IA) corticosteroids. However, prolonged courses of oral NSAIDs are associated with systemic adverse effects and repeat IA corticosteroid injections may cause cartilage degeneration. IA NSAIDs may be an alternative therapy possibly minimizing systemic side effects while maintaining efficacy. Therefore, we sought to summarize the pharmacokinetics, safety and efficacy of IA NSAIDs to help providers make a more informed decision on the use of IA NSAIDs.

Methods

We searched the National Library of Medicine Database with terms “intraarticular and nsaid”, yielding 1032 results. Only traditional formulations of NSAIDs were considered for inclusion. Animal studies were included if animals were healthy or if the method of arthritis induction was a reasonable model of osteoarthritis. Human studies were included if humans were healthy or if the primary disease studied was osteoarthritis of a large joint. Of 1032 results, 31 research articles met the inclusion criteria and were summarized in this review.

Results and Discussion

We found that single doses of IA NSAIDs provided far less total systemic and synovial exposure compared to a one week course of oral NSAIDs, but maximum concentrations to the synovium with IA administration were much higher. IA NSAIDs had an excellent safety profile in small animals, large animals and humans, although these injections were associated with non‐specific cartilage inflammation in healthy animals. In animal models, IA NSAIDs had similar efficacy to PO NSAIDs in treating OA‐related pain. In humans, IA NSAIDs had similar efficacy to PO NSAIDS and IA corticosteroids in treating OA‐related pain; however, many trials did not have a placebo control and outcome measures were heterogeneous.

What is new and Conclusion

Overall, single doses of IA NSAIDs appear safe and efficacious across animals and humans. The optimal use of IA NSAIDs is still to be determined and further research is needed. However IA NSAIDs may be an additional beneficial therapy to treat OA‐related pain. Potential uses may be to augment IA corticosteroids injections, to interrupt multiple IA corticosteroid injections or as an alternative in patients that are high risk for corticosteroid‐related adverse events.

Long-term anti-inflammatory effects of injectable celecoxib nanoparticle hydrogels for Achilles tendon regeneration

The treatment of chronic Achilles tendonitis (AT) often requires prolonged therapy and invasive therapeutic methods such as surgery or therapeutic endoscopy. To prevent the progression of chronic AT, excessive inflammation must be alleviated at an early stage. Corticosteroids or nonsteroidal anti-inflammatory drugs are generally prescribed to control inflammation; however, the high doses and long therapeutic periods required may lead to serious side effects. Herein, a local injectable poly(organophosphazene) (PPZ) - celecoxib (CXB) nanoparticle (PCNP) hydrogel system with long-term anti-inflammatory effects was developed for the treatment of tendonitis. The amphiphilic structure and thermosensitive mechanical properties of PPZ means that the hydrophobic CXB can be easily incorporated into the hydrophobic core to form PCNP at 4 °C. Following the injection of PCNP into the AT, PCNP hydrogel formed at body temperature and induced long-term local anti-inflammatory effects via sustained release of the PCNP. The therapeutic effects of the injectable PCNP system can alleviate excessive inflammation during the early stages of tissue damage and boost tissue regeneration. This study suggests that PCNP has significant potential as a long-term anti-inflammatory agent through sustained nonsteroidal anti-inflammatory drugs (NSAIDs) delivery and tissue regeneration boosting. STATEMENT OF SIGNIFICANCE: In the treatment of Achilles tendinitis, a long-term anti-inflammatory effect is needed to alleviate excessive inflammation and induce regeneration of the damaged Achilles tendon. Injectable poly(organophosphazene)(PPZ)-celecoxib(CXB) nanoparticles (PCNP) generated a long-term, localized-anti-inflammatory effect in the injected region, which successfully induced the expression of anti-inflammatory cytokines and suppressed pro-inflammatory cytokines, while the PCNPs degraded completely. Accordingly, regeneration of the damaged Achilles tendon was achieved through the long-term anti-inflammatory effect induced by a single PCNP injection. The PCNP system therefore has great potential in long-term NSAIDs delivery for various tissue engineering applications.

In vivo pharmacokinetic evaluation of carprofen delivery from intra-articular nanoparticles in rabbits: A population modelling approach

Osteoarthritis is treated with COX or fosfolipase A2 inhibitors such as carprofen, a propionic acid NSAID. The enhancement of its action over the articular cartilage is mandatory to facilitate its therapeutic application. Drug uptake into the cartilage requires high synovial fluid concentrations, anticipating its rapid distribution towards bloodstream. Thus, intraarticular administration improves local targeting of the drug, lining with the site of action. A pharmacokinetic study in rabbits has been performed to evaluate carprofen nanoparticles after intraarticular administration. Pharmacokinetic analysis of plasma profiles through a modelling approach, has demonstrated the rapid distribution of drug outside of synovial chamber but mainly remaining in plasma. The data modelling has demonstrated the existence of two release-absorption processes when the nanoparticles are administered in the synovial space. Additionally, results are predictive of the PK profile of some other species such as cat, dogs or humans.

Hyaluronan-Loaded Liposomal Dexamethasone-Diclofenac Nanoparticles for Local Osteoarthritis Treatment

Osteoarthritis (OA) remains one of the common degenerative joint diseases and a major cause of pain and disability in older adult individuals. Oral administration of non-steroidal anti-inflammatory drugs (NSAIDs) (such as diclofenac, DIC) or intra-articular injected gluco-corticosteroids (such as dexamethasone, DEX) were the conventional treatment strategies for OA to reduce joint pain. Current limitations for both drugs including severe adverse effects with risks of toxicity were noted. The aim of the present study was to generate a novel OA treatment formulation hyaluronic acid (HA)-Liposomal (Lipo)-DIC/DEX to combat joint pain. The formulation was prepared by constructing DIC with DEX-loaded nanostructured lipid carriers Lipo-DIC/DEX mixed with hyaluronic acid (HA) for prolonged OA application. The prepared Lipo-DIC/DEX nanoparticles revealed the size as 103.6 ± 0.3 nm on average, zeta potential as −22.3 ± 4.6 mV, the entrapment efficiency of 90.5 ± 5.6%, and the DIC and DEX content was 22.5 ± 4.1 and 2.5 ± 0.6%, respectively. Evidence indicated that HA-Lipo-DIC/DEX could reach the effective working concentration in 4 h and sustained the drug-releasing time for at least 168 h. No significant toxicities but increased cell numbers were observed when HA-Lipo-DIC/DEX co-cultured with articular chondrocytes cells. Using live-animal In vivo imaging system (IVIS), intra-articular injection of each HA-Lipo-DIC/DEX sufficed to reduce knee joint inflammation in OA mice over a time span of four weeks. Single-dose injection could reduce the inflammation volume down to 77.5 ± 5.1% from initial over that time span. Our results provided the novel drug-releasing formulation with safety and efficiency which could be a promising system for osteoarthritis pain control.

Chondroprotective Actions of Selective COX-2 Inhibitors In Vivo: A Systematic Review

Knee osteoarthritis (OA) is a condition mainly characterized by cartilage degradation. Currently, no effective treatment exists to slow down the progression of OA-related cartilage damage. Selective COX-2 inhibitors may, next to their pain killing properties, act chondroprotective in vivo. To determine whether the route of administration is important for the efficacy of the chondroprotective properties of selective COX-2 inhibitors, a systematic review was performed according to the PRISMA guidelines. Studies investigating OA-related cartilage damage of selective COX-2 inhibitors in vivo were included. Nine of the fourteen preclinical studies demonstrated chondroprotective effects of selective COX-2 inhibitors using systemic administration. Five clinical studies were included and, although in general non-randomized, failed to demonstrate chondroprotective actions of oral selective COX-2 inhibitors. All of the four preclinical studies using bolus intra-articular injections demonstrated chondroprotective actions, while one of the three preclinical studies using a slow release system demonstrated chondroprotective actions. Despite the limited evidence in clinical studies that have used the oral administration route, there seems to be a preclinical basis for considering selective COX-2 inhibitors as disease modifying osteoarthritis drugs when used intra-articularly. Intra-articularly injected selective COX-2 inhibitors may hold the potential to provide chondroprotective effects in vivo in clinical studies.

Intra-articular multifunctional celecoxib loaded hyaluronan nanocapsules for the suppression of inflammation in an osteoarthritic rat model

Direct intra-articular delivery of drugs to osteoarthritic joints offers the possibility of delivering high drug concentrations at the site of action as well as decreasing long term associated side effects after oral drug delivery. So in the current work, we aimed to improve the osteoarthritic therapeutic efficacy of the non-steroidal anti-inflammatory drug; celecoxib, through the formulation of drug loaded hyaluronan nanocapsules. The proposed formulation aimed to combine the beneficial viscosupplemental properties of hyaluronic acid with the pharmacological, anti-inflammatory, effect of celecoxib in a novel drug carrier for intra-articular delivery. The proposed nanocapsules were prepared by the nanoprecipitation method. Several formulation variables were studied aiming at optimizing the nanocapsules' size, polydispersity index and celecoxib entrapment efficiency %. The optimized hyaluronan nanocapsules formulation showed a size of 254.9 ± 3.06 nm, which is appropriate for the intra-articular delivery of celecoxib, high entrapment efficiency% of 97.98% ± 0.19, and prolonged celecoxib release for almost one week. The transmission electron microscope images revealed spherical shape of the nanocapsules with distinct shell and core structure. The in-vivo evaluation of the anti-osteoarthritic activity of the optimized hyaluronan nanocapsules formulation showed the superiority of the prepared celecoxib nanocapsules compared to celecoxib suspension in a Monoiodoacetate induced osteoarthritic rat model, regarding histological, swelling and immunohistochemical parameters of osteoarthritis.

Anti-Osteoarthritic Effects of a Mixture of Dried Pomegranate Concentrate Powder, Eucommiae Cortex, and Achyranthis Radix 5:4:1 (g/g) in a Surgically Induced Osteoarthritic Rabbit Model

In this study, we aimed to determine the synergistic effects of a formula consisting of dried pomegranate concentrate powder, Eucommiae Cortex, and Achyranthis Radix 5:4:1 (g/g) (PCP:EC:AR) in a surgically induced osteoarthritis (OA) rabbit model. PCP:EC:AR was orally administered once per day. Knee thickness, maximum extension of the knee joint, gross articular defect area, and the histopathological appearance of the cartilage were monitored, along with serum collagen type II C-telopeptide (CTX-II), cartilage oligomeric matrix protein (COMP), matrix metalloproteinase (MMP)-3, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and subchondral IL-1β and TNF-α levels. Roentgenographic images were also evaluated. PCP:EC:AR significantly inhibited the surgically induced increase in knee thickness, maximum extension of both knees, knee thickness after capsule exposure, gross femoral and tibial articular defect areas, loss of the knee joint area, serum and synovial COMP, CTX-II, and MMP expression, and synovial IL-1β, and TNF-α expression. In addition, surgically induced narrowing of the knee bones, loss of the joint area, cartilage damage, and osteophyte formation were reduced. PCP:EC:AR suppressed the surgically induced increases in the Mankin score, and subchondral IL-1β and TNF-α immunolabeled cell numbers. PCP:EC:AR exerted potent OA protective effects in a surgically induced OA rabbit model.

Osteochondral Tissue Chip Derived From iPSCs: Modeling OA Pathologies and Testing Drugs

Osteoarthritis (OA) is a chronic disease mainly characterized by degenerative changes in cartilage, but other joint elements such as bone are also affected. To date, there are no disease-modifying OA drugs (DMOADs), owing in part to a deficiency of current models in simulating OA pathologies and etiologies in humans. In this study, we aimed to develop microphysiological osteochondral (OC) tissue chips derived from human induced pluripotent stem cells (iPSCs) to model the pathologies of OA. We first induced iPSCs into mesenchymal progenitor cells (iMPCs) and optimized the chondro- and osteo-inductive conditions for iMPCs. Then iMPCs were encapsulated into photocrosslinked gelatin scaffolds and cultured within a dual-flow bioreactor, in which the top stream was chondrogenic medium and the bottom stream was osteogenic medium. After 28 days of differentiation, OC tissue chips were successfully generated and phenotypes were confirmed by real time RT-PCR and histology. To create an OA model, interleukin-1β (IL-1β) was used to challenge the cartilage component for 7 days. While under control conditions, the bone tissue promoted chondrogenesis and suppressed chondrocyte terminal differentiation of the overlying chondral tissue. Under conditions modeling OA, the bone tissue accelerated the degradation of chondral tissue which is likely via the production of catabolic and inflammatory cytokines. These findings suggest active functional crosstalk between the bone and cartilage tissue components in the OC tissue chip under both normal and pathologic conditions. Finally, a selective COX-2 inhibitor commonly prescribed drug for OA, Celecoxib, was shown to downregulate the expression of catabolic and proinflammatory cytokines in the OA model, demonstrating the utility of the OC tissue chip model for drug screening. In summary, the iPSC-derived OC tissue chip developed in this study represents a high-throughput platform applicable for modeling OA and for the screening and testing of candidate DMOADs.

Bioresponsive microspheres for on-demand delivery of anti-inflammatory cytokines for articular cartilage repair

Despite innovations in surgical interventions, treatment of cartilage injury in osteoarthritic joints remains a challenge due to concomitant inflammation. Obstructing a single dominant inflammatory cytokine has shown remarkable clinical benefits in rheumatoid arthritis, and similar strategies are being suggested to target inflammatory pathways in osteoarthritis (OA). Here, we describe the utility of gelatin microspheres that are responsive to proteolytic enzymes typically expressed in arthritic flares, resulting in on-demand and spatiotemporally controlled release of anti-inflammatory cytokines for cartilage preservation and repair. These microspheres were designed with a net negative charge to sequester cationic anti-inflammatory cytokines, and the magnitude of the negative charge potential increased with an increase in crosslinking density. Collagenase-mediated degradation of the microspheres was dependent on the concentration of the enzyme. Release of anti-inflammatory cytokines from the loaded microspheres directly correlated with the degradation of the gelatin matrix. Exposure of the IL-4 and IL-13 loaded microspheres reduced the inflammation of chondrocytes up to 80%. Hence, the delivery of these microspheres in an OA joint can attenuate the stimulation of chondrocytes and the resulting secretion of catabolic factors such as proteinases and nitric oxide. The microsphere format also allows for minimally invasive delivery and is less susceptible to mechanically induced drug release. Consequently, bioresponsive microspheres can be an effective tool for cartilage preservation and arthritis treatment.

The effects of intra-articular injection of ibuprofen on knee joint cartilage and synovium in rats

Objective

The aim of this animal study was to investigate the short and long-term local histomorphologic effects and the utility of intra-articular application of ibuprofen.

Methods

Forty-six Wistar Albino rats were used in the study. The rats were randomized into 5 groups of 8 and a sham group of 6. The 40 rats in the study groups were anaesthetised with 60 mg/kg of ketamine, then 0.25 ml ibuprofen (25 mg) was injected to the right knee joint of each rat (ibuprofen group) and 0.25 ml 0.9% saline to the left knee joint as the control group. To the 6 rats in the sham group, only puncture was applied to both knee joints. The rats in each of the 5 study groups were sacrificed on days 1, 2, 7, 14 and 21 respectively. The histomorphologic changes were graded on a 6-point scale regarding inflammation of the synovia, cartilage tissue, and subchondral bone. Inflammation scores were compared using the Mann Whitney U-test and comparisons of the sacrifice day and drug used were evaluated with the Kruskal Wallis test. The p values below 0.05 were considered as significant.

Results

Statistically significant difference was found between the ibuprofen injected knees (10/40) and the saline injected (0/40) and sham knees (0/12) in respect of hematoma positivity (p = 0.002). Significantly higher inflammation scores were found in ibuprofen injected knees on the 1st, 2nd, 7th and 14th days compared to controls and sham (p < 0.05). Inflammation scores were similar in ibuprofen injected knees with and without hematoma (p > 0.05). Inflammation of the ibuprofen injected group was most severe on day one and the severity of inflammation reduced gradually throughout the 3 weeks.

Conclusion

Our results show that intra-articular injection of ibuprofen can cause intra-articular hematoma. It also leads to transient inflammation of the synovia that is more severe in the early period, which gradually recovers.

Intra-articular injection of hydrogen sulfide decreased the progression of gonarthrosis

Hydrogen sulfide (H₂S) is found in both the plasma and synovial fluid of patients with gonarthrosis. In the present study, we investigated whether intra-articular injection of sodium hydrosulfide (NaSH) (1 mM, 30 μL), a H₂S donor, might affect gonarthrosis in rats. Gonarthrosis was induced surgically in the left knees of rats and left for 6 weeks for the development of disease. Then, intra-articular injections of NaSH or methylprednisolone (1 mg/kg, 30 μL) were administered to rats. Half of each group was sacrificed at the end of the first day and the other half was sacrificed at the end of 4 weeks to evaluate early and later effects of injections on gonarthrosis. The injury induced by anterior cruciate ligament resection and medial meniscectomy in rats caused the development of gonarthrosis. As the duration lengthened after gonarthrosis induction, the progression of the disease continued. According to the modified Mankin Scoring System, intra-articular injection of NaSH histopathologically slowed the progression of gonarthrosis, whereas methylprednisolone was ineffective. In addition, NaSH decreased apoptosis in rat knees with gonarthrosis. Each treatment did not cause injury to healthy knees. Our results lead to the consideration that intra-articular NaSH administration may be effective in the progression of gonarthrosis.

Disease-modifying effects of COX-2 selective inhibitors and non-selective NSAIDs in osteoarthritis: a systematic review

Osteoarthritis (OA) is a potentially disabling disease whose progression is dependent on several risk factors. OA management usually involves the use of non-steroidal anti-inflammatory drugs (NSAIDs) that are the primary pharmacological treatments of choice. However, NSAIDs have often been associated with unwanted side effects. Cyclooxygenase (COX)-2 specific inhibitors, such as celecoxib, have been successfully used as an alternative in the past for OA treatment and have demonstrated fewer side effects. While abundant data are available for the clinical efficacy of drugs used for OA treatment, little is known about the disease-modifying effects of these agents. A previous review published by Zweers et al. (2010) assessed the available literature between 1990 and 2010 on the disease-modifying effects of celecoxib. In the present review, we aimed to update the existing evidence and identify evolving concepts relating to the disease-modifying effects of not just celecoxib, but also other NSAIDs. We conducted a review of the literature published from 2010 to 2016 dealing with the effects, especially disease-modifying effects, of NSAIDs on cartilage, synovium, and bone in OA patients. Our results show that celecoxib was the most commonly used drug in papers that presented data on disease-modifying effects of NSAIDs. Further, these effects appeared to be mediated through the regulation of prostaglandins, cytokines, and direct changes to tissues. Additional studies should be carried out to assess the disease-modifying properties of NSAIDs in greater detail.

Protective Effect of Tetrandrine in a Rabbit Model of Osteoarthritis

Objectives

This study aims to investigate the antiinflammatory effect of tetrandrine in a rabbit model of osteoarthritis.

Patients and methods

The cruciate ligaments and medial menisci of 36 female New Zealand white rabbits (each weighing 2.0-3.0 kg) were resected. Six weeks after surgery, the animals were randomly divided into three groups (n=12 in each): tetrandrine (20 mg/kg/day), indomethacin (3 mg/kg/day) and control (saline 10 mL/day) groups. After 14 days of treatment, the results were assessed by macroscopic observation, histological evaluation, measurement of the levels of interleukin-1 beta, tumor necrosis factor-alpha and nitric oxide in the synovial fluid and messenger ribonucleic acid expression of metalloproteinase-3 in synovia.

Results

In the tetrandrine group, the pathological changes were more attenuated than in the control group. Levels of interleukin-1 beta, tumor necrosis factor-alpha, nitric oxide and metalloproteinase-3 in the synovial fluid or synovium were all significantly suppressed in the tetrandrine group compared with the control group. There were no significant differences between the tetrandrine and indomethacin groups.

Conclusion

The results of this study demonstrate that tetrandrine may protect against the development of experimentally induced osteoarthritis.

Sustained intra-articular release of celecoxib in an equine repeated LPS synovitis model

Synovial inflammation is an important characteristic of arthritic disorders like osteoarthritis and rheumatoid arthritis. Orally administered non-steroidal anti-inflammatory drugs (NSAIDs) such as celecoxib are among the most widely prescribed drugs to manage these debilitating diseases. Intra-articular delivery in biodegradable in situ forming hydrogels overcomes adverse systemic effects and prolongs drug retention in the joint. In this study two formulations of celecoxib (40 mg/g and 120 mg/g) in a propyl-capped PCLA-PEG-PCLA triblock copolymer were sequentially evaluated in a multiple LPS challenge equine synovitis model. Intra-articular release and systemic exposure to celecoxib and local changes at joint level were evaluated longitudinally. A single intra-articular injection of the high dose (HCLB)-gel or low dose (LCLB)-gel showed a sustained and controlled intra-articular release in both inflamed and healthy joints together with very low systemic exposure. Synovitis and lameness were moderate respectively very mild in this model due to the low concentration LPS (0.25 ng/joint). Both celecoxib formulations had a mild, transient effect on inflammatory and structural synovial fluid biomarkers but these returned to baseline within one week of administration. The HCLB-gel showed a significant inhibition in peak white blood cell concentration at 8 h after LPS induction. Elevated levels of celecoxib were observed in the joint for up to 30 days but no overall anti-inflammatory effects could be observed, which was thought to be due to the moderate synovitis. As there were no long-term adverse effects, sustained intra-articular release of celecoxib from in situ forming hydrogels should be evaluated further for its effects on longer-term relief of inflammatory joint pain in humans and animals.

Bioadhesive Polymersome for Localized and Sustained Drug Delivery at Pathological Sites with Harsh Enzymatic and Fluidic Environment via Supramolecular Host-Guest Complexation

Targeted and sustained delivery of drugs to diseased tissues/organs, where body fluid exchange and catabolic activity are substantial, is challenging due to the fast cleansing and degradation of the drugs by these harsh environmental factors. Herein, a multifunctional and bioadhesive polycaprolactone-β-cyclodextrin (PCL-CD) polymersome is developed for localized and sustained co-delivery of hydrophilic and hydrophobic drug molecules. This PCL-CD polymersome affords multivalent crosslinking action via surface CD-mediated host-guest interactions to generate a supramolecular hydrogel that exhibits evident shear thinning and efficient self-healing behavior. The co-delivery of small molecule and proteinaceous agents by the encapsulated PCL-CD polymersomes enhances the differentiation of stem cells seeded in the hydrogel. Furthermore, the PCL-CD polymersomes are capable of in situ grafting to biological tissues via host-guest complexation between surface CD and native guest groups in the tissue matrix both in vitro and in vivo, thereby effectively extending the retention of loaded cargo in the grafted tissue. It is further demonstrated that the co-delivery of small molecule and proteinaceous drugs via PCL-CD polymersomes averts cartilage degeneration in animal osteoarthritic (OA) knee joints, which are known for their biochemically harsh and fluidically dynamic environment.

Tenascin-C Prevents Articular Cartilage Degeneration in Murine Osteoarthritis Models

Objective The objective of this study was to determine whether intra-articular injections of tenascin-C (TNC) could prevent cartilage damage in murine models of osteoarthritis (OA). Design Fluorescently labeled TNC was injected into knee joints and its distribution was examined at 1 day, 4 days, 1 week, 2 weeks, and 4 weeks postinjection. To investigate the effects of TNC on cartilage degeneration after surgery to knee joints, articular spaces were filled with 100 μg/mL (group I), 10 μg/mL (group II) of TNC solution, or control (group III). TNC solution of 10 μg/mL was additionally injected twice after 3 weeks (group IV) or weekly after 1 week, 2 weeks, and 3 weeks (group V). Joint tissues were histologically assessed using the Mankin score and the modified Chambers system at 2 to 8 weeks after surgery. Results Exogenous TNC was maintained in the cartilage and synovium for 1 week after administration. Histological scores in groups I and II were better than scores in group III at 4 and 6 weeks, but progressive cartilage damage was seen in all groups 8 weeks postoperatively. Sequential TNC injections (groups IV and V) showed significantly better Mankin score than single injection (group II) at 8 weeks. Conclusion TNC administered exogenously remained in the cartilage of knee joints for 1 week, and could decelerate articular cartilage degeneration in murine models of OA. We also showed that sequential administration of TNC was more effective than a single injection. TNC could be an important molecule for prevention of articular cartilage damage.

Effects of hyaluronic acid combined with anti-inflammatory drugs compared with hyaluronic acid alone, in clinical trials and experiments in osteoarthritis: a systematic review and meta-analysis

Background

The objectives are to compare the efficacy of intra-articular hyaluronic acid (IA-HA) alone and in combination with anti-inflammatory drugs (IA-HA + AI), corticosteroids (CS) or non-steroidal anti-inflammatory drugs (NSAIDs) in clinical trials and in vivo and in vitro studies of osteoarthritis (OA).

Methods

Data in the BIOSIS, CINAHL, Cochrane Library, EMBASE and Medline databases were collected and analyzed. Random effects models were used to compute the effect size (ES) of the mean difference in pain reduction scores from baseline and the relative risk (RR) of adverse events. The ES of histological scores in vivo and cartilage metabolism in vitro were also calculated. We conducted sensitivity analysis of blinding and intention-to-treat (ITT), compared IA-HA combined with CS vs. IA-HA alone in trials, and compared the effects of HA + AI vs. AI alone in vitro, including anabolic and catabolic gene expression.

Results

Thirteen out of 382 papers were included for data analysis. In clinical trials, the ES of pain reduction scores within the 1st month was −4.24 (−6.19, −2.29); 2nd–12th month, −1.39 (−1.95, −0.82); and within one year, −1.63 (−2.19, −1.08), favoring IA-HA + AI (P < 0.001). The ES of RR was 1.08 (0.59, 1.98), and histological scores was 1.38 (−0.55, 3.31). The ES of anabolic gene expression was 1.22 (0.18, 2.25), favoring HA alone (P < 0.05); catabolic gene expression was 0.74 (−0.44, 1.53), favoring HA alone; and glycosaminoglycans remaining was −2.45 (−5.94, 1.03).

Conclusions

IA-HA + AI had greater efficacy for pain relief than IA-HA alone within a one-year period. However, HA + AI down-regulated the ACAN gene when compared with HA alone in vitro.

Therapeutic Efficacy of Ozone Injection into the Knee for the Osteoarthritis Patient along with Oral Celecoxib and Glucosamine

Introduction

Suffering from osteoarthritis is prevalent among elderly patients so the use of intra-articular injection of medical ozone may well be the effective way to relieve their pain.

Aim

To evaluate the effect of intra-articular injection of medical ozone given into the knee of the osteoarthritis patients, and to compare it with taking celecoxib and glucosamine orally.

Materials and Methods

In the present study, 76 patients suffering from osteoarthritis were randomly assigned into two groups. In the ozone group, 20 ml ozone-oxygen mixture gas concentration of 20 μg/ml was injected into knee articular cavity and each patient took oral celecoxib and glucosamine hydrochloride. Patients in control group only took the celecoxib and glucosamine hydrochloride orally.Pain score and Lysholm knee score were measured prior to the injection (pretreatment) and at one, three, six weeks after the beginning of the treatment (posttreatment).

Results

After the treatment, the pain intensity and function significantly improved in the two groups compared with the pretreatment (p<0.05). In the ozone group, three weeks after intervention, the pain score improved significantly when compared with the control group (p<0.05).After the treatment, the lysholm scores increased significantly (p<0.05), but in the ozone group, it improved faster.

Conclusion

Intra-articular injection of ozone plus oral celecoxib and glucosamine could significantly decrease pain intensity in patients with mild to moderate Knee Osteoarthritis (KOA), and improve their functional status early than oral celecoxib and glucosamine only.

Protective effect of Shenmai injection on knee articular cartilage of osteoarthritic rabbits and IL-1β-stimulated human chondrocytes

Shenmai injection (SMI) has been widely used as a therapy to treat a number of diseases. However, its anti-osteoarthritic properties have not yet been fully investigated. In the present study, the protective effect of SMI on knee articular cartilage of anterior cruciate ligament transected rabbits and interleukin-1β (IL-1β)-stimulated human chondrocytes was investigated. For the in vivo study, knee osteoarthritis (KOA) was induced in female New Zealand white rabbits by anterior cruciate ligament transection (ACLT) in the knee of right hind limb. Rabbits either underwent sham surgery or ACLT surgery. Out of the rabbits receiving ACLT surgery, half of the rabbits received one 0.3 ml Shenmai intra-articular injection in the knee per week for four weeks, following ACLT surgery. The other rabbits received the same volume of normal saline solution. The cartilage was subsequently collected for histological evaluation. For the in vitro study, cultured human chondrocytes were treated with 10 ng/ml IL-1β in the presence or absence of 5 and 2% (v/v) SMI for 24 h. Nitric oxide (NO) and prostaglandin E2 (PGE2) levels in cell culture supernatant were assessed using a Griess reaction and ELISA respectively. The mRNA expression of cyclooxgenase-2 (COX-2), inducible nitric oxide synthase (iNOS), matrix metalloproteinase (MMP)-1, MMP-13 and tissue inhibitors of metalloproteinase-1 (TIMP-1) in chondrocytes were detected by reverse transcription-quantitative polymerase chain reaction. The results of the current study revealed that treatment with SMI ameliorated cartilage degradation in the ACLT rabbit model, and decreased levels of NO and PGE2. Furthermore, treatment with SMI decreased levels of COX-2, iNOS, MMP-1 and MMP-13 mRNA expression and increased TIMP-1 mRNA expression in IL-1β-stimulated human chondrocytes. These results indicate that SMI suppresses inflammation and ameliorated cartilage degradation, making it a potential and promising therapeutic option to treat KOA.

Celecoxib-loaded PEA microspheres as an auto regulatory drug-delivery system after intra-articular injection

In this study, we investigated the potential of celecoxib-loaded polyester amide (PEA) microspheres as an auto-regulating drug delivery system for the treatment of pain associated with knee osteoarthritis (OA). Celecoxib release from PEA microspheres and inflammation responsive release of a small molecule from PEA was investigated in vitro. Inflammation responsive release of a small molecule from PEA was observed when PEA was exposed to cell lysates obtained from a neutrophil-like Hl-60 cell line. Following a short initial burst release of ~15% of the total drug load in the first days, celecoxib was slowly released throughout a period of >80days. To investigate biocompatibility and degradation behavior in vivo, celecoxib-loaded PEA microspheres were injected in OA-induced (ACLT+pMMx) or contralateral healthy knee joints of male Lewis rats. Bioactivity of celecoxib from loaded PEA microspheres was confirmed by PGE₂ measurements in total rat knee homogenates. Intra-articular biocompatibility was demonstrated histologically, where no cartilage damage or synovial thickening and necrosis were observed after intra-articular injections with PEA microspheres. Degradation of PEA microspheres was significantly higher in OA induced knees compared to contralateral healthy knee joints, while loading the PEA microspheres with celecoxib significantly inhibited degradation, indicating a drug delivery system with auto regulatory behavior. In conclusion, this study suggests the potential of celecoxib-loaded PEA microspheres to be used as a safe drug delivery system with auto regulatory behavior for treatment of pain associated with OA of the knee.

Ibuprofen-loaded porous microspheres suppressed the progression of monosodium iodoacetate-induced osteoarthritis in a rat model

The objectives of this study were (1) to fabricate ibuprofen-loaded porous microspheres (IBU/PMSs), (2) to evaluate the in vitro anti-inflammatory effects of the microspheres using LPS-induced inflammation in cultured synoviocytes, and (3) to evaluate the in vivo effect of the IBU/PMSs on the progression of monosodium iodoacetate (MIA)-induced osteoarthritis (OA) in a rat model. A dose-dependent in vitro anti-inflammatory effect on pro-inflammatory cytokine markers (matrix metallopeptidase-3 (MMP-3), matrix metallopeptidase-13 (MMP-13), cyclooxygenase-2 (COX-2), a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5)), interleukin-6 (IL-6), and tumor necrosis factor (TNF-α) was observed by confirming with real-time PCR analyses. In vivo, treatment with IBU/PMSs reduced MIA-stimulated mRNA expression of MMP-3, MMP-13, COX-2, ADAMTS-5, IL-6, and TNF-α in rat synoviocytes. In addition, we demonstrated that intra-articular IBU/PMSs suppressed the progression of MIA-induced OA in the rat model via anti-inflammatory mechanisms. In conclusion, IBU/PMSs are a promising therapeutic material to control the pain and progression of OA.

Parathyroid hormone(1-34) exhibits more comprehensive effects than celecoxib in cartilage metabolism and maintaining subchondral bone micro-architecture in meniscectomized guinea pigs

OBJECTIVE

To evaluate the effects of PTH(1-34) on cartilage, subchondral bone mass and structure in medial meniscectomized guinea pigs and compare them to those of celecoxib (CLX).

METHOD

Forty-eight 3-month-old male Hartley albino guinea pigs received either sham or medial meniscectomy (MNX) operations. One week after the procedure, meniscectomized animals began 12 weeks of treatment by oral administration of CLX (20 mg/kg, daily), subcutaneous injection of PTH (1-34) (24 μg/kg, 5 days/week), or normal saline for MNX group. All animals were euthanized 12 weeks later, cartilage degeneration and subchondral bone micro-architecture was analyzed.

RESULTS

OARSI scores indicated cartilage degeneration was partially inhibited by either CLX or PTH(1-34). Cartilage was significantly thicker in PTH(1-34)-treated animals than in CLX-treated animals. Both CLX and PTH(1-34) treatment were associated with lower ADAMTS-4 and periostin expression than MNX. MMP-13 expression in PTH(1-34) group was significantly lower than that in CLX group. However, AGG expression and the ratio of Col-II/MMP-13 expression in PTH(1-34) group were significantly higher than in the CLX group. Micro-CT analysis showed BMD, BV/TV, and Tb.Th levels to be significantly lower in the MNX group and CLX groups than in the sham group, but these parameters were significantly higher in the PTH(1-34) group than in either the MNX group or CLX group.

CONCLUSIONS

Both CLX and PTH(1-34) exhibits protective effects on cartilage degeneration in meniscectomized guinea pigs. However, PTH(1-34) exhibited superior performance to CLX not only in metabolism of cartilage tissue but also in maintenance of subchondral bone micro-architecture.

Intra-articular hyaluronate, tenoxicam and vitamin E in a rat model of osteoarthritis: evaluation and comparison of chondroprotective efficacy

OBJECTIVE

The aim of this experimental study was to evaluate and compare the chondroprotective efficacy of intra-articular hyaluronic acid, tenoxicam and vitamin E in osteoarthritis.

METHODS

An osteoarthritis model was created by anterior cruciate ligament transection and medial menisectomy in knees of 28 rats. The rats were randomized into four groups; first group served as a control group and received intra-articular injections of saline solution, intra-articular HA, intra-articular tenoxicam and intra-articular Vit E were applied to the treatment groups. First intra-articular injections were applied at second week postoperatively and repeated once a week for 5 weeks. At 8th week after the operation groups were compared based on the histologic scores of cartilage degeneration by Mankin Histological Grading Scale.

RESULTS

Total cartilage degeneration score was significantly increased in the control group (P=0.004). Total Mankin scores of HA, tenoxicam and Vit E groups were significantly lower than the control group (P=0.004, P=0.016, P=0.012 respectively). There was no statistically siginificant difference between the treatment groups in terms of total Mankin scores (P>0.05).

CONCLUSION

Intra-articular application of HA, tenoxicam and Vit E are chondroprotective in early osteoarthritis model in rats. Chondroprotective activity of tenoxicam and Vit E are comparable with the beneficial effects of HA on articular cartilage.

Intra-articular tibiofemoral injection of a nonsteroidal anti-inflammatory drug has no detrimental effects on joint mechanics in a rat model

Administration of intra-articular medications, including corticosteroids and analgesics, is common clinical practice for knee pathology and dysfunction. Non-steroidal anti-inflammatory drugs (NSAIDs) are another category of medication commonly prescribed for their analgesic and anti-inflammatory properties. Recent studies demonstrated the efficacy of injectable NSAIDs in the treatment of intra-articular pathology and postoperative analgesia. However, little data exist regarding the safety of intra-articular injection, despite the increase in its application. Therefore, we investigated the effects of intra-articular NSAID injection on articular cartilage, the anterior cruciate ligament (ACL), and joint function in the rat. Sixty-four Sprague-Dawley rats were divided into either saline (SAL) or ketorolac (NSAID) tibiofemoral single injection treatment groups. Animals were euthanized at 2, 7, 28, and 84 days post-injection for histological and mechanical analyses. Additionally, a subset of animals underwent longitudinal ambulatory evaluation to determine joint functional properties. We hypothesized that intra-articular ketorolac injection would result in no detrimental mechanical, histological, or functional changes. No differences were reported between the NSAID and SAL groups in any of the parameters measured at any time point, demonstrating the potential safety of intra-articular NSAID administration. Therefore, NSAID injection could be further considered for clinical application in humans.

Anti-inflammatory strategies in cartilage repair

Cartilage defects are normally concomitant with posttraumatic inflammation and pose a major challenge in cartilage repair. Due to the avascular nature of cartilage and its inability to surmount an inflammatory response, the cartilage is easily attacked by proinflammatory factors and oxidative stress; if left untreated, osteoarthritis may develop. Suppression of inflammation has always been a crux for cartilage repair. Pharmacological drugs have been successfully applied in cartilage repair; however, they cannot optimally work alone. This review article will summarize current pharmacological drugs and their application in cartilage repair. The development of extracellular matrix-based scaffolds and preconditioned tissue-specific stem cells will be emphasized because both of these tissue engineering components could contribute to an enhanced ability not only for cartilage regeneration but also for anti-inflammation. These strategies could be combined to boost cartilage repair under inflammatory conditions.

Protective effect of a new biomaterial against the development of experimental osteoarthritis lesions in rabbit: a pilot study evaluating the intra-articular injection of alginate-chitosan beads dispersed in an hydrogel

OBJECTIVE

This study aimed to evaluate the structural benefit of a new biomaterial composed of alginate-chitosan (AC) beads dispersed in a hydrogel (H) derived from chitosan on the development of osteoarthritis (OA) in rabbit.

DESIGN

OA was induced by the surgical transection of the anterior cruciate ligament in rabbits. Animals received a single intra-articular injection (900 μl) of AC beads in H hydrogel, H hydrogel alone or saline a week after surgery. OA development was followed by X-rays. Blood samples were collected throughout the study to measure biological markers (Prostaglandins E2 - PGE2 and C reactive protein - CRP). Macroscopic observation and histological evaluation of articular cartilage and synovial membrane were performed 6 weeks after surgery.

RESULTS

AC beads in H hydrogel prevented from the development of OA based on the reduction of the Kellgren & Lawrence (K&L) score. It also significantly reduced the histological score of cartilage lesion severity. This effect was homogenous on every joint compartment. It was due to a significant effect on cartilage structure and cellularity scores. The injection of AC beads in H hydrogel also tended to reduce the synovial membrane inflammation. No significant variation of biological markers was noted.

CONCLUSIONS

The present pilot study provides interesting and promising results for the use of AC beads in H hydrogel in animal. It indeed prevented the development of OA cartilage lesions without inflammatory signs. The potencies of this biomaterial to protect OA joint should be further documented. It could then represent a new alternative for viscosupplementation in human OA management.

Preliminary histopathological study of intra-articular injection of a novel highly cross-linked hyaluronic acid in a rabbit model of knee osteoarthritis

Osteoarthritis is a degenerative joint disease mostly occurring in the knee and commonly seen in middle-aged and elderly adults. Intra-articular injection of hyaluronic acid has been widely used for treatment of knee osteoarthritis. The aim of this study was to evaluate the efficacy of intra-articular injection of a novel highly cross-linked hyaluronic acid, alone or in combination with ropivacaine hydrochloride and triamcinolone acetonide, on knee articular cartilage in a rabbit model of collagenase-induced knee osteoarthritis. After induction of experimental osteoarthritis by intra-articular injection of collagenase, adult New Zealand white rabbits (n = 12) were divided into 3 groups. Group 1 (control group) received 0.3 ml phosphate buffered saline into the right knee joint. Group 2 received 0.3 ml cross-linked hyaluronic acid (33 mg/ml) into the right knee joint. Group 3 received a mixture of 0.15 ml cross-linked hyaluronic acid (33 mg/ml), 0.05 ml ropivacaine hydrochloride 1 % and 0.1 ml triamcinolone acetonide (10 mg/ml) into the right knee joint. Intra-articular injections were given 4 weeks after first collagenase injection and were administered once a week for 3 weeks. Gross pathology and histological evaluation of rabbits’ knee joints were performed after 16 weeks following initial collagenase injection. Histological analysis of sections of right knee joints at lesion sites showed a significant decrease in Mankin’s score in groups treated with hyaluronic acid alone or in combination with ropivacaine hydrochloride and triamcinolone acetonide versus control group (p < 0.05 and p < 0.01 respectively). This evidence was consistent with strong articular degenerative changes in control right knee joints (grade III osteoarthritis), while the treated groups revealed less severe articular degenerative changes (grade II osteoarthritis). The present results show that cross-linked hyaluronic acid, alone or in combination with ropivacaine hydrochloride and triamcinolone acetonide, produces a significant improvement in knee articular cartilage degeneration in a rabbit model of collagenase-induced osteoarthritis.

Celecoxib, a selective cyclooxygenase-2 inhibitor, attenuates renal injury in a rat model of Cisplatin-induced nephrotoxicity

BACKGROUND

Cisplatin is an effective chemotherapeutic agent successfully used in the treatment of a wide range of tumors. Nevertheless, nephrotoxicity has restricted its clinical use. Recent studies have strongly suggested that inflammatory mechanisms may play an important role in the pathogenesis of cisplatin nephrotoxicity. Celecoxib, a selective cyclooxygenase-2 inhibitor used as anti-inflammatory, may therefore have a protective effect on cisplatin-induced renal injury.

METHODS

In the present study, rats were injected intraperitoneally with a single dose of cisplatin (7 mg/kg) and/or celecoxib (30 mg/kg) for 5 days.

RESULTS

Nephrotoxicity manifested biochemically by elevations in serum creatinine, blood urea nitrogen, and proteinuria, and an increase in kidney weight as a percentage of total body weight. In addition, a marked decrease in serum albumin was observed. Lipid peroxidation in the kidney was monitored by measuring the malondialdehyde level and glutathione content, which were increased and depleted, respectively. Administration of celecoxib with cisplatin attenuated cisplatin-induced changes in kidney function parameters and oxidative stress markers. Histopathological examination of the kidney confirmed these results.

CONCLUSION

In conclusion, this study indicates that celecoxib may be a promising drug for clinical use as a nephroprotectant against cisplatin-induced nephrotoxicity.