Isolated and combined effects of photobiomodulation therapy, topical nonsteroidal anti-inflammatory drugs, and physical activity in the treatment of osteoarthritis induced by papain

Osteoarthritis (OA) is a chronic inflammatory disease and is characterized as a degenerative process. This study aimed to evaluate and compare the effects of a topical nonsteroidal anti-inflammatory drug (NSAID), physical activity, and photobiomodulation therapy (PBMT) applied alone and/or in combination between them in an experimental model of knee OA. OA was induced by injection of papain in the knees of rats. After 21 days, the animals started to be treated with the above treatment. Histological analysis shows that the experimental model of OA induction causes morphological changes consistent with the disease, and among treatments, the PBMT is the most effective for reducing these changes. Moreover, the results demonstrate that PBMT and NSAID reduce the total number of cells in the inflammatory infiltrate (p<0.05) and PBMT was the most effective for reducing the activity of myeloperoxidase (p<0.05). Finally, we observed that both NSAID and PBMT were effective for reducing the gene expression of MMP-3 (p<0.05), but in relation to the gene expression of MMP-13, PBMT was the most effective treatment (p<0.05). The results of this study indicate that PBMT is the most effective therapy in stopping disease progression, and improving inflammatory conditions observed in OA.

The electroacupuncture-induced analgesic effect mediated by 5-HT1, 5-HT3 receptor and muscarinic cholinergic receptors in rat model of collagenase-induced osteoarthritis

BACKGROUND

Osteoarthritis (OA) is an degenerative disease characterized by chronic joint pain. Complementary and alternative treatment such as acupuncture have been utilized to alleviate pain. The objective of this study was to investigate the analgesic mechanisms of electroacupuncture (EA) in the collagenase-induced osteoarthritis (CIOA) rat model.

METHODS

Four weeks after inducing CIOA by injecting collagenase solution into the left knee of 5-week-old male Sprague-Dawley rats, 2 Hz and 100 Hz EA on Zusanli (ST 36) was performed. The analgesic effect of EA was evaluated by the tail flick latency (TFL) and paw pressure threshold (PPT) tests. To investigate the analgesic mechanism, serotonergic and muscarinic cholinergic receptor agonists and antagonists were injected 20 min prior to EA and the resultant changes were evaluated by the TFL and PPT tests.

RESULTS

EA on Zusanli (ST 36) demonstrated an analgesic effect in the CIOA rat model. The 2 Hz EA treatment showed a significantly greater analgesic effect than the 100 Hz treatment. The analgesic effect of 2 Hz EA was not strengthened by 5-HT1, 5-HT2, 5-HT3, and muscarinic cholinergic receptor agonist pretreatment, was blocked by 5-HT1, 5-HT3, and muscarinic cholinergic receptor antagonist pretreatment, but not blocked by 5-HT2 receptor antagonist pretreatment.

CONCLUSIONS

In the CIOA rat model, EA on Zusanli (ST 36) exhibited analgesic effects, and 2 Hz EA resulted in a significantly greater analgesic effect than 100 Hz EA. The analgesic effect of 2 Hz EA was reduced by pretreatment of 5-HT1 receptor, 5-HT3 receptor and muscarinic cholinergic receptor antagonists.

Effects of Balsamodendron mukul Gum Resin Extract on Articular Cartilage in Papain-induced Osteoarthritis

Context • Osteoarthritis (OA) is one of the most prevalent chronic diseases of the musculoskeleton, causing functional disability among older adults. Management of OA includes conventional pharmacological treatments consisting primarily of nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, physiotherapy, and surgical procedures. The medications are not ideal therapeutic agents; NSAIDs in particular can cause serious side effects. Objective • The study was conducted to investigate the effects of Balsamodendron mukul (BDM) gum resin extract on cartilage damage and microstructural changes in the subchondral bone of rats with papain-induced, osteoarthritic knee joints. Design • The authors designed a parallel randomized, controlled study to examine the effects of 3 concentrations of BDM on OA in a murine model. Setting • The present study was undertaken at the research laboratory, Faculty of Biological Engineering, Shobhit University (Modipuram, Meerut, India). Intervention • OA was induced by intra-articular injections of 0.2 mL of 4% papain solution and 0.1 mL of 0.03 M cysteine through the patellar ligament using a 26-gauge, 1.27-cm needle. The rats in the sham group received same volume of isotonic sodium chloride solution. The rats were divided into 6 groups : (1) control group-fresh rats, with ages and genders similar to those of the other groups but with no induction of OA and no treatments; (2) sham group-rats receiving a sham induction of OA using an intra-articular injection of saline of the same volume as the papain given to all OA rats but no treatments; (3) OA group-rats induced with OA but receiving no treatments; (4) OA + BDM (10%) group-rats induced with OA that received a 10% dose of BDM; (5) OA + BDM (20%) group-rats induced with OA that received a 20% dose of BDM; and (6) OA + BDM (40%) group-rats induced with OA that received a 40% dose of BDM. Rats in the treatment groups were fed their respective doses of BDM extract for 30 d. Outcome Measures • The articular cartilages from the knee joints and epiphyseal bones of the femur and tibia were extracted from the right- and left-side limbs to perform the biochemical, microarchitectural, and histological analyses. Results • The total protein and collagen content of the articular cartilage of the knees were significantly higher in all treated groups when compared with the OA group of rats. The histological analysis revealed a thicker cartilage and a higher trabecular density of the subchondral bone (epiphyseal bone) in BDM-treated rats. Conclusions • The oral dose of BDM gum resin extract was shown to relieve OA pain, regenerate the cartilaginous matrix, and increase the subchondral bone components. On the basis of the findings, the research team suggests that the BDM gum resin extract may be used for therapeutic interventions for reversal of OA and reduction in its related inflammatory pain.

Anti-Osteoarthritic Effects of the Litsea japonica Fruit in a Rat Model of Osteoarthritis Induced by Monosodium Iodoacetate

Osteoarthritis (OA) is a degenerative chronic disease that affects various tissues surrounding the joints, such as the subchondral bone and articular cartilage. The onset of OA is associated with uncontrolled catabolic and anabolic remodeling processes of the joints, including the cartilage and subchondral bone, to adapt to local biological and biochemical signals. In this study, we determined whether 70% ethanolic (EtOH) extract of Litsea japonica fruit (LJFE) had beneficial effects on the articular cartilage, including structural changes in the tibial subchondral bone, matrix degradation, and inflammatory responses, in OA by using a rat model of monosodium iodoacetate-induced OA. Our results showed that administration of LJFE increased the bone volume and cross-section thickness, but the mean number of objects per slice in this group was lower than that in the OA control (OAC) group. In addition, the LJFE decreased the expression of inflammatory cytokines. Compared to the OAC group, the group treated with high doses of LJFE (100 and 200 mg/kg) showed a more than 80% inhibition of the expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases. Our results suggest that LJFE can be used as a potential anti-osteoarthritic agent.

Anti-inflammatory and chondroprotective effects of atorvastatin in a cartilage explant model of osteoarthritis

OBJECTIVE

This study aimed to assess the chondroprotective potential of atorvastatin in rat's cartilage explant culture model of osteoarthritis, stimulated by interleukin-1β (IL-1β).

MATERIALS AND METHODS

The cartilage explants were treated with 20 ng/ml IL-1β alone or with 20 ng/ml IL-1β + various concentration of atorvastatin (1, 3, or 10 µM dissolved in DMSO) and incubated at 37 °C for 24 h. Also, control (0.25% DMSO), stimulated (20 ng IL-1β) and treatment (atorvastatin 10 µM) cartilage explants were incubated without and with 1400W (10 µM). After 24 h of incubation, TNF-α, PGE2, MMP-13, TIMP-1, NO, and superoxide anion formation (O2(-)) concomitant with glycosaminoglycans (GAGs) were estimated in the medium.

RESULTS

Atorvastatin inhibited IL-1β-induced GAGs release, TNF-α, MMP-13, and O2(-) with no effect on TIMP-1 and NO. In addition, the source of NO in normal and atorvastatin-treated cartilage was eNOS, while for IL-1β-stimulated cartilage it was iNOS. The cartilage degradation was associated with the combined effects of increased NO and O2 (-) rather than only NO.

CONCLUSION

The present study suggests that atorvastatin has the ability to protect cartilage degradation following IL-1β-stimulated cartilage in in vitro OA model and supports additional therapeutic application of atorvastatin in OA.

Effect of Intra-articular Injection of AOD9604 with or without Hyaluronic Acid in Rabbit Osteoarthritis Model

BACKGROUND

To investigate the effects of AOD9604 intra-articular injections with or without hyaluronic acid (HA) in a collagenase-induced knee osteoarthritis (OA) rabbit model.

DESIGN

Mature New Zealand white rabbits (n=32) were randomly administered 2 mg collagenase type II twice in each knee joint. Weekly injections of 0.6 mL saline (Group 1), 6 mg HA (Group 2), 0.25 mg AOD9604 (Group 3), and 0.25 mg AOD9604 with 6 mg HA (Group 4) were administered for 4-7 weeks after the first intra-articular collagenase injection. The degree of cartilage degeneration was assessed using morphological and histopathological findings, and the degree of lameness was observed at 8 weeks after the first collagenase injection.

RESULTS

Mean gross morphological and histopathological scores were significantly higher in Group 1 than in Groups 2, 3, and 4, and the scores were significantly lower in Group 4 than in Groups 2 and 3. The lameness period in Group 4 was significantly shorter than those in Groups 1, 2, and 3. The lameness period in Group 1 was significantly longer than those in Groups 2 and 3.

CONCLUSION

Intra-articular AOD9604 injections using ultrasound guidance enhanced cartilage regeneration, and combined AOD9604 and HA injections were more effective than HA or AOD9604 injections alone in the collagenase-induced knee OA rabbit model.

PTH [1-34]-induced alterations of the subchondral bone provoke early osteoarthritis

OBJECTIVE

To test the hypothesis that changes in the subchondral bone induced by parathyroid hormone (PTH [1-34]) reciprocally affect the integrity of the articular cartilage within a naïve osteochondral unit in vivo.

DESIGN

Daily subcutaneous injections of 10 μg PTH [1-34]/kg were given to adult rabbits for 6 weeks, controls received saline. Blood samples were continuously collected to monitor renal function. The subchondral bone plate and subarticular spongiosa of the femoral heads were separately assessed by micro-computed tomography. Articular cartilage was evaluated by macroscopic and histological osteoarthritis scoring, polarized light microscopy, and immunohistochemical determination of type-I, type-II, type-X collagen contents, PTH [1-34] receptor and caspase-3 expression. Absolute and relative extents of hyaline and calcified articular cartilage layers were measured histomorphometrically. The correlation between PTH-induced changes in subchondral bone and articular cartilage was determined.

RESULTS

PTH [1-34] enhanced volume, mineral density, and trabecular thickness within the subarticular spongiosa, and increased thickness of the calcified cartilage layer (all P < 0.05). Moreover, PTH [1-34] led to cartilage surface irregularities and reduced matrix staining (both P < 0.03). These early osteoarthritic changes correlated with and were ascribed to the increased thickness of the calcified cartilage layer (P = 0.026) and enhanced mineral density of the subarticular spongiosa (P = 0.001).

CONCLUSIONS

Modifications of the subarticular spongiosa by PTH [1-34] cause broadening of the calcified cartilage layer, resulting in osteoarthritic cartilage degeneration. These findings identify a mechanism by which PTH-induced alterations of the normal subchondral bone microarchitecture may provoke early osteoarthritis.

Calcium phosphate particulates increase friction in the rat knee joint

OBJECTIVE

Basic calcium phosphate (BCP) particulates are commonly found in cartilage and synovial fluid of osteoarthritis (OA) joints with the amount of BCP correlating with knee OA severity. How cartilage mineralization affects joint degeneration has yet to be determined. The objective of this study was to determine whether BCP in the synovial fluid affects the rat knee joint coefficient of friction (COF).

METHODS

The COFs of knees from both hind limbs of four mature male rats were measured post mortem using a pendulum apparatus with an infrared tracking system. The three conditions evaluated were (1) the naïve state, (2) after the injection of 100 μL of phosphate buffered saline (PBS) (sham) and (3) after the injection of 100 μL of a 1 mg/mL BCP suspension. The decrease in the pendulum amplitude (decay) was fit using two friction models: (1) a one parameter Stanton linear decay model and (2) a two parameters combination Stanton linear decay and viscous damping exponential decay model.

RESULTS

The COF increased 17.6% after injection of BCP compared to the naïve (P = 0.0012) and 16.0% compared to the saline injected (P = 0.0018) joints as derived from the one parameter model. The COF did not differ between naïve and saline injected joints. Results from the two parameters model showed a similar increase in COF after injection of BCP while the viscous damping was not significantly different between conditions.

CONCLUSIONS

The increased joint friction with BCP particulates suggests BCPs may play a role in articular surface degradation and OA development.

Chondroprotective activity of a detoxicated traditional Chinese medicine (Fuzi) of Aconitum carmichaeli Debx against severe-stage osteoarthritis model induced by mono-iodoacetate

ETHNOPHARMACOLOGICAL RELEVANCE

Fuzi is an effective but toxic traditional Chinese medicine (TCM) derived from Aconitum carmichaeli. In our previous study, detoxicated Fuzi (d-Fuzi) has been originally developed with no toxicity but significant efficacy. However, whether d-Fuzi can be used for therapy of osteoarthritis (OA), remain unknown.

MATERIALS AND METHODS

Severe OA model was established by intra-articular mono-iodoacetate (MIA) injection (1.25mg) into rats and orally treated with 2g/ml d-Fuzi at a dosage of 7 ml/kg body weight for 28 days. In vivo, the articular radiographic and histopathologic analyses were performed to qualitatively assess the chondroprotective effect of d-Fuzi, followed by quantitative measurements of bone density and Mankin scores. In vitro, such effect on chondrocyte viability after MIA attack was evaluated. Hybrid quadrupole time-of-flight mass spectrometry (QTOF-MS) was performed for chemical analysis of d-Fuzi.

RESULTS

d-Fuzi was demonstrated to possess chondroprotective activity on MIA-induced OA model by in vivo preventing the articular degeneration and the reducing of bone density and Mankin score, as well as by in vitro promoting the chondrocyte proliferation and inhibiting the MIA-induced chondrocyte damage. A total of 23 compounds were identified in d-Fuzi, most of which were deduced as the non-toxic derivatives of aconite alkaloids.

CONCLUSIONS

This is the first report regarding chondroprotective effect and chemical profile of d-Fuzi, originally revealing its great anti-OA potential and thereby providing a promising TCM candidate for OA therapy.

The inhibition of subchondral bone lesions significantly reversed the weight-bearing deficit and the overexpression of CGRP in DRG neurons, GFAP and Iba-1 in the spinal dorsal horn in the monosodium iodoacetate induced model of osteoarthritis pain

BACKGROUND

Chronic pain is the most prominent and disabling symptom of osteoarthritis (OA). Clinical data suggest that subchondral bone lesions contribute to the occurrence of joint pain. The present study investigated the effect of the inhibition of subchondral bone lesions on joint pain.

METHODS

Osteoarthritic pain was induced by an injection of monosodium iodoacetate (MIA) into the rat knee joint. Zoledronic acid (ZOL), a third generation of bisphosphonate, was used to inhibit subchondral bone lesions. Joint histomorphology was evaluated using X-ray micro computed tomography scanning and hematoxylin-eosin staining. The activity of osteoclast in subchondral bone was evaluated using tartrate-resistant acid phosphatase staining. Joint pain was evaluated using weight-bearing asymmetry, the expression of calcitonin gene-related peptide (CGRP) in the dorsal root ganglion (DRG), and spinal glial activation status using glial fibrillary acidic protein (GFAP) and ionized calcium binding adaptor molecule-1 (Iba-1) immunofluorescence. Afferent neurons in the DRGs that innervated the joints were identified using retrograde fluorogold labeling.

RESULTS

MIA injections induced significant histomorphological alterations and joint pain. The inhibition of subchondral bone lesions by ZOL significantly reduced the MIA-induced weight-bearing deficit and overexpression of CGRP in DRG neurons, GFAP and Iba-1 in the spinal dorsal horn at 3 and 6 weeks after MIA injection; however, joint swelling and synovial reaction were unaffected.

CONCLUSIONS

The inhibition of subchondral bone lesions alleviated joint pain. Subchondral bone lesions should be a key target in the management of osteoarthritic joint pain.

Coenzyme Q10 ameliorates pain and cartilage degradation in a rat model of osteoarthritis by regulating nitric oxide and inflammatory cytokines

Objective

To investigate the effect of CoenzymeQ10 (CoQ10) on pain severity and cartilage degeneration in an experimental model of rat osteoarthritis (OA).

Materials and Methods

OA was induced in rats by intra-articular injection of monosodium iodoacetate (MIA) to the knee. Oral administration of CoQ10 was initiated on day 4 after MIA injection. Pain severity was assessed by measuring secondary tactile allodynia using the von Frey assessment test. The degree of cartilage degradation was determined by measuring cartilage thickness and the amount of proteoglycan. The mankin scoring system was also used. Expressions of matrix metalloproteinase-13 (MMP-13), interleukin-1β (IL-1β), IL-6, IL-15, inducible nitric oxide synthase (iNOS), nitrotyrosine and receptor for advanced glycation end products (RAGE) were analyzed using immunohistochemistry.

Results

Treatment with CoQ10 demonstrated an antinociceptive effect in the OA animal model. The reduction in secondary tactile allodynia was shown by an increased pain withdrawal latency and pain withdrawal threshold. CoQ10 also attenuated cartilage degeneration in the osteoarthritic joints. MMP-13, IL-1β, IL-6, IL-15, iNOS, nitrotyrosine and RAGE expressions were upregulated in OA joints and significantly reduced with CoQ10 treatment.

Conclusion

CoQ10 exerts a therapeutic effect on OA via pain suppression and cartilage degeneration by inhibiting inflammatory mediators, which play a vital role in OA pathogenesis.

Silymarin potentiates the anti-inflammatory effects of Celecoxib on chemically induced osteoarthritis in rats

Silymarin (SMN) is used as an antioxidant complex to attenuate the pro-oxidant effects of toxic agents. This study was carried out to investigate the effect of SMN, Celecoxib (CLX) individually and in combination on monoiodoacetate (MIA)-induced osteoarthritis (OA) in rat. Forty adult Wistar rats were assigned to control and test groups. Animals in the test group following OA induction were subdivided into 4 subgroups according to the treatment profile: OA(+); received saline normal (5ml/kg, b.w.), OA(+)CLX(+); received CLX (100mg/kg, orally), OA(+)SMN(+), received SMN (50mg/kg, orally), and OA(+)CLX(+)SMN(+), received both CLX and SMN. The animals received test compounds by gastric gavage for 14 consecutive days. Animals in the OA(+) group showed a significant (p<0.01) increase in serum and synovial levels of IL-1β, while both test compounds reduced the IL-1β level. Both CLX and SMN lowered the OA-increased level of malondialdehyde by 77% and 79% and nitric oxide by 73% and 76%, respectively, in the synovial tissue. Special safranin O (SO) histopathological staining revealed that CLX and SMN improved the MIA-induced destruction and fibrillation in cartilage surface. CLX and SMN regulated the MIA-up regulated IL-1β at mRNA level. The combination therapy resulted in an additive effect between CLX and SMN in biochemical, histopathological and molecular assays. These findings suggest that SMN exerts anti-inflammatory effect and also potentiates the anti-inflammatory effect of CLX on MIA-induced OA. The anti-inflammatory property of SMN may attribute to its antioxidant capacity, which affects the proinflammatory mediators at translational and transcriptional level.

Anti-inflammatory and anti-osteoarthritis effects of fermented Achyranthes japonica Nakai

ETHNOPHARMACOLOGICAL RELEVANCE

Achyranthyes japonica Nakai (AJN) has been traditionally used to control pain and improve dysfunction in osteoarthritis (OA) patients.

AIM OF THE STUDY

The objectives of the present study were to investigate anti-inflammatory and anti-osteoarthritis activities of fermented AJN (FAJN).

MATERIALS AND METHODS

Anti-inflammatory activity of non-fermented AJN (NFAJN) and FAJN was evaluated by in vitro assay using LPS-induced RAW 264.7 cells. In addition, their cartilage protective effects were also determined in vitro assay using SW1353 cell and in vivo model system using collagenase-induced arthritis (CIA) in rabbits. Moreover, we isolated and identified 20-hydroxyecdysone (20-HES) as a marker component in FAJN.

RESULT

FAJN showed stronger anti-inflammatory activity than NFAJN through inhibiting production of NO and PGE2 in LPS-induced RAW 264.7, and lowering levels of MMP-3 release in SW1353 cells treated with TNF-a. FAJN contained higher levels of 20-HES, as a marker component, than AJN. FAJN ameliorates the progress of OA by inhibiting local inflammation. It does this by regulating levels of TNF-a and IL-4, and protecting articular cartilage by preventing destruction of proteoglycan, collagens, and also preventing injury to chondrocytes.

CONCLUSION

Therefore, FAJN is a potential therapeutic agent for reduction of cartilage damage that occurs in OA.

Chondroprotective and anti-inflammatory effects of sesamin

Osteoarthritis (OA) is a major disability of elderly people. Sesamin is the main compound in Sesamun indicum Linn., and it has an anti-inflammatory effect by specifically inhibiting Δ5-desaturase in polyunsaturated fatty acid biosynthesis. The chondroprotective effects of sesamin were thus studied in a porcine cartilage explant induced with interleukin-1beta (IL-1β) and in a papain-induced osteoarthritis rat model. With the porcine cartilage explant, IL-1β induced release of sulfated-glycosaminoglycan (s-GAG) and hydroxyproline release, and this induction was significantly inhibited by sesamin. This ability to inhibit these processes might be due to its ability to decrease expression of MMP-1, -3 and -13, which can degrade both PGs and type II collagen, both at the mRNA and protein levels. Interestingly, activation of MMP-3 might also be inhibited by sesamin. Moreover, in human articular chondrocytes (HACs), some pathways of IL-1β signal transduction were inhibited by sesamin: p38 and JNK. In the papain-induced OA rat model, sesamin treatment reversed the following pathological changes in OA cartilage: reduced disorganization of chondrocytes in cartilage, increased cartilage thickness, and decreased type II collagen and PGs loss. Sesamin alone might increase formation of type II collagen and PGs in the cartilage tissue of control rats. These results demonstrate that sesamin efficiently suppressed the pathological processes in an OA model. Thus, sesamin could be a potential therapeutic strategy for treatment of OA.

The monosodium iodoacetate model of osteoarthritis pain in the rat

Osteoarthritis (OA) is one form of degenerative joint disease characterized by progressive loss of articular cartilage, decreased function and is frequently accompanied by chronic pain. Given the success of arthroplasty as a treatment for late-stage OA, there is considerable interest in developing therapies pertaining to the management of pain associated with OA as well as therapies designed to slow or reverse the progression of the disease. To this end, establishment of relevant animal models that are amenable to testing novel therapies is of considerable value to the scientific community. Here, we describe a model of OA-related pain in which progressive joint destruction is induced by injection of monosodium iodoacetate into the articular space of the knee of the rat. Further, we describe three different methods to measure pain-related behaviors in this model: hind limb weight bearing, primary mechanical hyperalgesia, and hind limb grip strength.

Determination of specific neuropeptides modulation time course in a rat model of osteoarthritis pain by liquid chromatography ion trap mass spectrometry

Animal models are useful to evaluate pharmacological therapies to alleviate joint pain. The present study characterized central neuropeptides modulation in the monoiodoacetate (MIA) rat model. Animals receiving a single 3mg MIA injection were euthanized at 3, 7, 14, 21 and 28 days post injection. Spinal cords were analyzed by liquid chromatography ion trap mass spectrometry. Up-regulations of the calcitonin gene-related peptide and substance P were observed starting on days 7 and 28 respectively, whereas big dynorphin(₁₋₃₂) content decreased significantly on day 14 in comparison to control animals (P<0.05). Preclinical drug evaluations using this model should be conducted between 7 and 21 days post injection when the lesions resemble most to human osteoarthritis.

Sodium iodoacetate induced osteoarthrosis model in rabbit temporomandibular joint: CT and histological study (part I)

Studies to elucidate the pathophysiology of osteoarthrosis have been hampered by the lack of a rapid, reproducible animal model that mimics the histopathology and symptoms associated with the disease. The aim of this study is to evaluate the radiological, histological and histomorphometrical findings of four different concentrations of sodium iodoacetate (MIA) to create osteoarthrosis by using an arthrocentesis technique on rabbit temporomandibular joint (TMJ). 12 New Zealand white male rabbits received an injection of MIA (50 μl dose of 1.5, 2, 2.5, 3mg/ml concentrations) to a single joint of each group by arthrocentesis. Computed tomography (CT) images were obtained pre- and post-injections at 2, 4 and 6 weeks. Early osteoarthritic changes in the rabbit TMJ were found histologically at 4 weeks and with a 3mg/ml concentration of MIA. The mean subchondral bone volume depended on the concentration of MIA and was 62±2.6%, 63±4.1%, 42±3.6% and 38±3.8%, respectively. A minor abnormality was found on CT in six joints at the 4-week follow up. MIA injection and arthrocentesis offer a rapid and minimally invasive method of reproducing histologically osteoarthrotic lesions in the rabbit TMJ.

Monosodium iodoacetate-induced osteoarthritis produces pain-depressed wheel running in rats: implications for preclinical behavioral assessment of chronic pain

Pain stimulates some behaviors (e.g., withdrawal responses) and depresses other behaviors (e.g., feeding and locomotion). We are developing methods for testing candidate analgesics using measurements of pain-depressed behaviors. Such assays may model important aspects of clinical pain and complement traditional procedures that measure pain-stimulated behaviors. The present study characterized the effects of a chronic pain manipulation (monosodium iodoacetate (MIA)-induced osteoarthritis) on wheel running in rats. Rats had 24 h voluntary access to running wheels. Duration of running wheel acquisition was manipulated such that rats had either 21 or 7 days of running wheel access prior to MIA administration. Wheel running was monitored for an additional 21 days following MIA administration. MIA produced concentration- and acquisition length-dependent decreases in wheel running. Parallel experiments demonstrated that MIA produced concentration-dependent tactile allodynia and shifts in hind limb weight bearing. MIA was differentially potent across assays with a potency rank: weight-bearing≥von Frey>running wheel. MIA produced greater depression of wheel running in rats with relatively high baseline running rates compared to rats with relatively low baseline running rates. The differential potency of MIA across assays and apparent rate-dependent effects in running wheels may impact our traditional interpretations of preclinical nociceptive and antinociceptive testing.

Ongoing pain in the MIA model of osteoarthritis

Osteoarthritis (OA) is a chronic pain condition characterized by pain during joint use as well as pain at rest (i.e., ongoing pain). Although injection of monosodium iodoacetate (MIA) into the intra-articular space of the rodent knee is a well established model of OA pain that is characterized by changes in weight bearing and hypersensitivity to tactile and thermal stimuli, it is not known if this procedure elicits ongoing pain. Further, the time-course and possible underlying mechanisms of these components of pain remain poorly understood. In these studies, we demonstrated the presence of ongoing pain in addition to changes in weight bearing and evoked hypersensitivity. Twenty-eight days following MIA injection, spinal clonidine blocked changes in weight bearing and thermal hypersensitivity and produced place preference indicating that MIA induces ongoing and evoked pain. These findings demonstrate the presence of ongoing pain in this model that is present at a late-time point after MIA allowing for mechanistic investigation.

Monthly versus 3-monthly goserelin acetate treatment in pre-menopausal patients with estrogen receptor-positive early breast cancer

This study compared the efficacy and safety of a 3-monthly 10.8-mg depot goserelin (Zoladex(TM)) injection with the current 3.6 mg monthly dose in pre-menopausal Japanese women with estrogen receptor-positive (ER+) early breast cancer. This was a multicenter, open-label, randomized study. Primary endpoint was a non-inferiority analysis (10.8/3.6 mg) of the area under the concentration-time curve (AUC) of estradiol (E(2)) over the first 24 weeks. Secondary endpoints included E(2) and follicle-stimulating hormone (FSH) concentrations, menstruation, and safety and tolerability. In total, 170 patients were randomized to receive goserelin 10.8 mg every 3 months (n = 86) or 3.6 mg every month (n = 84). Mean AUCs for E(2) were similar between treatment groups (18.32 and 18.95 pg/ml·week for goserelin 10.8 and 3.6 mg, respectively). AUC ratio was 0.974 (95% confidence interval, 0.80, 1.19), indicating non-inferiority for goserelin 10.8 mg. Serum E(2) and FSH remained suppressed throughout the study and no patient experienced menses after week 16. No clinically important differences in safety and tolerability were observed between the two groups. In terms of E(2) suppression, 3-monthly goserelin 10.8 mg was non-inferior to monthly goserelin 3.6 mg in pre-menopausal women with ER+ breast cancer.

The analgesic and anti-inflammatory effect of WIN-34B, a new herbal formula for osteoarthritis composed of Lonicera japonica Thunb and Anemarrhena asphodeloides BUNGE in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Lonicera japonica Thunb and Anemarrhena asphodeloides BUNGE have been used for the treatment of a variety of inflammatory diseases, cold and infective diseases in many countries, including Korea and China.

AIM OF THE STUDY

This study aimed to assess the anti-nociceptive and anti-inflammatory activities of n-butanol fraction (WIN-34B) prepared from dried flowers of Lonicera japonica and dried roots of Anemarrhena asphodeloides as potential novel treatment of osteoarthritis.

MATERIALS AND METHODS

Anti-nociceptive activities of WIN-34B (100, 200 and 400 mg/kg, p.o.) were measured using acetic acid-induced writhing response, formalin-induced paw licking, hot plate, radiant heat tail-flick, carrageenan-induced paw pressure, and Hargreaves tests, respectively. Anti-inflammatory activities of WIN-34B (100, 200 and 400 mg/kg, p.o.) were assessed using acetic acid-induced vascular permeability, carrageenan-induced paw edema, and croton oil-induced ear edema. Anti-osteoarthritis effect of WIN-34B was analyzed using monosodium iodoacetate (MIA)-induced osteoarthritis animal model.

RESULTS

WIN-34B exhibited better anti-inflammatory activity than that of celecoxib in carrageenan at the dose of 200 mg/kg and croton oil-induced paw edema and ear edema at the doses of 200 and 400 mg/kg. WIN-34B exhibited significant anti-inflammatory effects on vascular permeability. WIN-34B also exhibited significant anti-nociceptive activities in the late phase of formalin-induced paw licking and writhing response model in mice. In radiant heat tail-flick and carrageenan-induced paw pressure tests, WIN-34B at the dose of 400 mg/kg and at the doses of 200 and 400 mg/kg presented similar activities to indomethacin and celecoxib. Compared to indomethacin WIN-34B at 400mg/kg showed similar or better anti-nociceptive activities after 1 and 2h of theraphy in the hot plate test and better anti-nociceptive activity than that of celecoxib in Hargreves test. In the MIA-induced osteoarthritis animal models, WIN-34B at 400 mg/kg exhibited similar or better anti-nociceptive property than that of celecoxib throughout the pain measurement periods.

CONCLUSION

When compared to celecoxib, WIN-34B exhibited similar or better anti-nociceptive and anti-inflammatory activities in osteoarthritic animal models, which may become a potential novel treatment for osteoarthritis.

Flare-up of hand osteoarthritis caused by zoledronic acid infusion

Zoledronic acid is effective for osteoporosis at a single annual intravenous dose. It usually causes few adverse effects; the most common are related to acute phase reactions. We reported the case of a 64-year-old woman who presented flare-up of hand osteoarthritis after zoledronic acid infusions. Despite the fact that arthralgia is a common side effect of intravenous bisphosphonates, development of inflammatory signs in osteoarthritic joints is a rare event. We hypothesized that this side effect is caused by a release of cytokines secondary to activation of gamma-delta T lymphocytes.

[The use of magnetic-laser therapy in the combined treatment of osteoarthrosis in workers exposed to inorganic fluoride compounds]

The present study included 67 patients who had been exposed to the impact of inorganic fluoride compounds. It demonstrated beneficial effect of magnetolaser therapy in combination with whole body iodine-bromide-sodium chlorine baths, physical exercises, and massage on clinical manifestations of the primary disease and concomitant pathologies. Simultaneously, metabolic processes in the articular cartilage and bone tissue were normalized, lipid peroxidation was improved and optimization of antioxidative protection achieved. These changes are indicative of high therapeutic efficiency of the combined treatment employed in this study and its favourable influence on the quality of life of the patients.

NSAIDs

INTRODUCTION

NSAIDs are widely used. Almost 10% of people in The Netherlands used a non-aspirin NSAID in 1987, and the overall use was 11 defined daily doses per 1000 population a day. In Australia in 1994, overall use was 35 defined daily doses per 1000 population a day, with 36% of the people receiving NSAIDs for osteoarthritis, 42% for sprain and strain or low back pain, and 4% for rheumatoid arthritis; 35% of the people receiving NSAIDs were aged over 60 years.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: Are there any important differences between oral NSAIDs? What are the effects of topical NSAIDs; and of co-treatments to reduce the risk of gastrointestinal adverse effects of oral NSAIDs? We searched: Medline, Embase, The Cochrane Library, and other important databases up to September 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 36 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the benefits and harms of the following interventions: differences in efficacy among different oral NSAIDs, between oral and topical NSAIDs, and between oral NSAIDs and alternative analgesics; dose-response relationship of oral NSAIDs; and H(2) blockers, misoprostol, or proton pump inhibitors to mitigate gastrointestinal adverse effects of oral NSAIDs.

Additive effects of intra-articular injection of growth hormone and hyaluronic acid in rabbit model of collagenase-induced osteoarthritis

In a rabbit model of collagenase-induced osteoarthritis, the additive effects of intra-articular recombinant human growth hormone (GH) administration to hyaluronic acid (HA) were evaluated. After intra-articular collagenase injection, mature New Zealand white rabbits (n=30) were divided into 3 groups. Group 1 (control rabbits) received once weekly intra-articular saline injections for 4 weeks. Group 2 rabbits received 6 mg HA injections, and group 3 rabbits were injected with 6 mg HA and 3 mg recombinant human GH. These injections were initiated 4 weeks after collagenase injections. Lameness was observed for 9 weeks after collagenase injections. Macroscopic and histopathological knee joint findings were also evaluated at the end of 9 weeks after collagenase injections. Although all animals had lameness after collagenase injections, the duration and severity of lameness were significantly shorter and less severe in group 3 than group 1 and 2 (P<0.01). Macroscopic scores showed that femoral condyles of group 3 rabbits received significantly less cartilage damage than those of groups 1 and 2 rabbits (P<0.01). Histopathological score was also the lowest in group 3 (P<0.01). These results suggest that co-injection of intra-articular HA and recombinant human GH is more effective than HA injections alone in an osteoarthritis model.

Protective effects of butanol fraction from Betula platyphyla var. japonica on cartilage alterations in a rabbit collagenase-induced osteoarthritis

AIM OF THIS STUDY

Many cartilage protective agents have been developed from natural products, and they have resulted in the development of treatments for osteoarthritis. In this study, we determined the osteoarthritic efficacy and mechanism of butanol fraction from the bark of Betula platyphylla var. japonica (BFBP) in collagenase-induced rabbit model of osteoarthritis (CIA).

MATERIALS AND METHODS

The right knees of rabbits were injected intra-articularly with collagenase, and rabbits were orally administrated with distilled water (vehicle), BFBP (50, 100 and 200 mg/kg) or celecoxib (100 mg/kg) once a day for 28 days after the initiation of the CIA.

RESULTS

Oral administration of BFBP dose-dependently suppressed the stiffness and global histologic score. Proteoglycan intensity was considerably increased in a dose-dependent manner. As well, the mRNA expression of MMP-1, and MMP-3 was decreased. On the contrary, the level of TIMP-1 in the synovial fluids was significantly increased in the BFBP treated group. The pathologic inflammatory molecules such as PGE2 and COX-2 were inhibited by BFBP, but COX-1 expression not affected.

CONCLUSION

We suggest that BFBP has shown the protective effect on cartilage alternations through balance of MMPs/TIMP-1 and regulates inflammatory-related molecules in vivo model of osteoarthritis, and great candidate for development of osteoarthritis treatment.

Real-time ultrasonic assessment of progressive proteoglycan depletion in articular cartilage

The loss of proteoglycan (PG) is regarded as one of the early signs of osteoarthritis (OA), thus observing the progress of PG loss would be useful for the early detection of OA. In this study, high-frequency ultrasound was used to monitor and analyze the trypsin-induced progressive degeneration in articular cartilage. Full thickness cartilage-bone specimens (n = 10) prepared from normal bovine patellae were digested using 0.25% trypsin solution for different periods of time to evaluate the dynamics of the digestion process. The trypsin penetration front was observed in M-mode image, which was acquired using a nominal 50 MHz focused transducer. The transient speed of the digestion process was estimated from the image. The digestion fraction, which represents the ratio of the digestion depth to the total cartilage thickness, was estimated from ultrasound data and histology sections. With ultrasound, the digestion fraction observed in the 10 specimens ranged from 64% to 99% and was correlated to that measured by histology (R(2) > or = 0.63, p < 0.05). It was found that the digestion speed decreased nonlinearly with depth from 0.61 +/- 0.16 microm/s (mean +/- SD) in the superficial zone to 0.04 +/- 0.02 microm/s in a region located at 70% of the cartilage thickness in depth. The relationship between the digestion depth and the exposure duration in trypsin could be described using a third order polynomial function. The full thickness of digested and undigested tissues was also measured using caliper, estimated from ultrasound data and histology sections, and compared. These findings indicate that ultrasound could provide useful information about the trypsin-induced progressive PG depletion in articular cartilage. Therefore, ultrasound represents a useful tool to evaluate the dynamics of models of OA in vitro in cartilage specimens in a research environment and this would ultimately help the in vitro examination of articular cartilage for research related to model of OA from the early stages of tissue degradation.

The effects of bone remodeling inhibition by alendronate on three-dimensional microarchitecture of subchondral bone tissues in guinea pig primary osteoarthrosis

We assessed whether increase of subchondral bone density enhances cartilage stress during impact loading, leading to progressive cartilage degeneration and accelerated osteoarthrosis (OA) progression. Sixty-six male guinea pigs were randomly divided into six groups. During a 9-week treatment period, four groups received twice-weekly subcutaneous injections of alendronate (ALN) in two doses: two groups received 10 microg/kg and two groups received 50 microg/kg. The two control groups received vehicle. After 9 weeks, one 10 microg/kg ALN group, one 50 microg/kg ALN group, and one control group were killed. The remaining three groups (17-week groups) were left for an additional 8 weeks, receiving the same treatment regimen before death. The left proximal tibiae were scanned by micro-computed tomography to quantify the microarchitecture of subchondral bone, followed by mechanical testing and determination of collagen and mineral. The control groups had typical OA-related cartilage degeneration at 9 and 17 weeks, whereas the 50 microg/kg ALN group had even worse degeneration in the medial condyle. It is unclear whether there is a direct or a secondary effect of ALN on the cartilage. The 9-week ALN group had significantly greater subchondral plate thickness. The 9- and 17-week groups had similar changes of cancellous bone microarchitecture, with greater volume fraction and connectivity and an extremely plate-like structure. The 9-week ALN group had greater bone mineral concentration, and the 17-week ALN group had reduced collagen concentration and greater mineral concentration. Treatment with ALN did not significantly change the mechanical properties of the cancellous bone.

The short-term therapeutic effect of recombinant human bone morphogenetic protein-2 on collagenase-induced lumbar facet joint osteoarthritis in rats

OBJECTIVE

To determine whether an intra-articular injection of recombinant human bone morphogenetic protein-2 (rhBMP-2) alleviates cartilage degradation in a rat model of osteoarthritis (OA) of the lumbar facet joint.

METHOD

The right-side facet joint OA model was created by an intra-articular injection of collagenase (type II) 2 weeks before treatment. The OA rats were divided into four groups: (1) no treatment, or intra-articular injection of either (2) saline, (3) rhBMP-2 10 ng, or (4) rhBMP-2 100 ng. The left-side facet joint served as the normal control. At 3 and 6 weeks after treatment, histological analyses were performed on the cartilage, synovium, subchondral bone and bone marrow. The cartilage and synovium were graded using a modified Mankin score and a synovium score system. Extracellular type II collagen was evaluated by immunohistochemistry.

RESULTS

Intra-articular injection of collagenase causes OA-like changes in the facet joint. OA rats treated with rhBMP-2 at both dosages tested showed reduced severity of their cartilage lesions compared with untreated and saline-treated groups. There was a statistically significant difference in the modified Mankin score compared to the untreated and saline-treated groups. However, some rhBMP-2-treated rats at the higher dose (100 ng) showed, as a side effect, joint space obliteration caused by cartilage overgrowth. Also OA rats treated with 100 ng of rhBMP-2 displayed a significant synovium reaction at 3 weeks compared with that in other groups. Immunohistochemical analysis showed that treatment with rhBMP-2 significantly increased the content of type II collagen.

CONCLUSION

This study demonstrates the potential efficacy of rhBMP-2 in the alleviation of arthritic changes in a rat model of OA of the lumbar facet joint. However, treatment with a high dosage of rhBMP-2 caused adverse side effects in some animals.

Transcriptional profiling and pathway analysis of monosodium iodoacetate-induced experimental osteoarthritis in rats: relevance to human disease

OBJECTIVE

The objective of this study was to characterize the rat monosodium iodoacetate (MIA)-induced model for osteoarthritis (OA) and determine the translatability of this model to human disease. This was accomplished through pathway, network and system level comparisons of transcriptional profiles generated from animal and human disease cartilage.

METHODS

An OA phenotype was induced in rat femorotibial joints following a single injection of 200mug MIA per knee joint for a period of 2 or 4 weeks. Lesion formation in the rat joints was confirmed by histology. Gene expression changes were measured using the Agilent rat whole genome microarrays. Cartilage was harvested from human knees and gene expression changes were measured using the Agilent human arrays.

RESULTS

One thousand nine hundred and forty-three oligos were differentially expressed in the MIA model, of these, approximately two-thirds were up-regulated. In contrast, of the 2130 differentially expressed oligos in human disease tissue, approximately two-thirds were down-regulated. This dramatic difference was observed throughout each level of the comparison. The total overlap of genes modulated in the same direction between rat and human was less than 4%. Matrix degradation and inflammatory genes were differentially regulated to a much greater extent in MIA than human disease tissue.

CONCLUSION

This study demonstrated, through multiple levels of analysis, that little transcriptional similarity exists between rat MIA and human OA derived cartilage. As disease modulatory activities for potential therapeutic agents often do not translate from animal models to human disease, this and like studies may provide a basis for understanding the discrepancies.

[Skeletal fluorosis: a case report]

The authors report a case of skeletal fluorosis described in a 60 years old man living in south-west Tunisian. The main clinical sign is a severe functional legs disability. Radiographic examination has shown a diffused osteocondensation, with cervical spine degenerative discopathy, a pelvis bilateral osteoarthritis and an interosseous membrane ossification of forearms and legs. The skeletal fluorosis diagnosis has been confirmed by high serum and urinary fluoride levels.

Synthesis and SAR of 2-aryl pyrido[2,3-d]pyrimidines as potent mGlu5 receptor antagonists

A novel series of potent 2-aryl pyrido[2,3-d]pyrimidine mGlu5 receptor antagonists are described. The synthesis and pharmacological activities of these analogs are discussed.

Erosive osteoarthritis during treatment with bevacizumab and paclitaxel in a patient with recurrent papillary serous carcinoma of the ovary

Bevacizumab (BVC) is currently used in recurrent ovarian cancer and as part of the initial treatment for ovarian cancer. The most serious toxicities associated with BVC include gastrointestinal perforations, delayed wound healing, and hemorrhage. Arthritis had never been addressed in patients who received BVC treatment. This is the first case report of arthritis emergence linked to BVC administration. A 59-year-old female with recurrent ovarian cancer received multiple hormonal and cytotoxic regimens for 5 years and then developed erosive osteoarthritis of the hands secondary to BVC and paclitaxel. This effect was confirmed by a significant improvement in her symptoms and signs, after treatment was discontinued.

Intracellular localisation of galectin-3 has a protective role in chondrocyte survival

OBJECTIVE

Although galectin-3 (gal-3) is expressed during arthritic disorders, the part it plays has never been described. The aim of the study was to determine the intracellular roles of gal-3 in chondrocytes and cartilage.

METHODS

Following treatment with sodium nitroprusside, a cell death inducer, intracellular levels of total and phosphorylated gal-3 were measured by immunoblots in human osteoarthritic (OA) chondrocytes. Cell viability was also assessed by the lactate dehydrogenase activity in conditioned media from OA chondrocytes or from ATDC5 cells transfected with a gal-3-expressing vector. After generating an OA model by intra-articular injection of 0.5% mono-iodoacetate (MIA), histological evaluation of articular cartilage and subchondral bone was performed in wild-type (WT) and gal-3 knockout (KO) mice aged 6 weeks and 4 months.

RESULTS

In vitro experiments demonstrated that intracellular gal-3 had a protective role in chondrocyte survival, which involved its phosphorylation. In contrast to 6-week-old mice, 4-month-old gal-3 KO mice, compared with WT mice, presented OA-like cartilage modifications. OA induction via MIA injection in WT mice generated cartilage lesions similar to those found in gal-3 KO animals. Moreover, OA induction showed a significant decrease in subchondral bone surface in the gal-3 KO mice in contrast to the WT group.

CONCLUSIONS

Altogether these findings indicate that intracellular gal-3 has a beneficial effect in articular cells, as its absence in KO mice led to cartilage lesions.

NSAIDs

INTRODUCTION

NSAIDs are widely used. Almost 10% of people in The Netherlands used a non-aspirin NSAID in 1987, and the overall use was 11 defined daily doses per 1000 population per day. In Australia in 1994, overall use was 35 defined daily doses per 1000 population a day, with 36% of the people receiving NSAIDs for osteoarthritis, 42% for sprain and strain or low back pain, and 4% for rheumatoid arthritis; 35% of the people receiving NSAIDs were aged over 60 years.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: Are there any important differences between NSAIDs? What are the effects of topical NSAIDs; and of co-treatments to reduce the risk of gastrointestinal adverse effects of NSAIDs? We searched: Medline, Embase, The Cochrane Library and other important databases up to December 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 35 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the benefits and harms of the following interventions: alternative analgesics, H(2) blockers, misoprostol, NSAIDs (systemic, topical, differences in efficacy between, dose-response relationship of), proton pump inhibitors.

Different effects of high molecular weight sodium hyaluronate and NSAID on the progression of the cartilage degeneration in rabbit OA model

OBJECTIVE

We examined the effects of nonsteroidal anti-inflammatory drug (NSAID) and intra-articular injections of sodium hyaluronate (HA) on cartilage degeneration in rabbit knee osteoarthritis (OA) model induced by partial meniscectomy.

METHODS

Loxoprofen sodium (LOX) was used as the NSAID, administered p.o. once daily for 14 days at a dose of 4 mg/kg, starting from the day of meniscectomy. Suvenyl(SVE) was used as the high molecular weight HA, injected intra-articularly into injured knee every 3 days from the day of surgery. The effect on pain was assessed by an Incapacitance Tester, and the damage of cartilage was evaluated by visual assessment and histopathology at 14 days after the surgery.

RESULTS

Hind paw weight bearing on the injured paw decreased time-dependently in the control group. In other three groups, the decrease of hind paw weight distribution was suppressed, demonstrating an analgesic effect. Visible damage and histopathological findings of cartilage degeneration were evident in the cartilages of the control group at day 14. In the SVE group, the damaged cartilage area decreased and cartilage degeneration was ameliorated. In contrast, in the LOX group, the cartilage degeneration was augmented compared with the control group. And, this exacerbated cartilage degeneration induced by LOX was reversed by the concomitant use of SVE.

CONCLUSION

Our data show that the treatment with high molecular weight HA from earlier stage is strongly recommended to preserve the structure of cartilage.

Effects of knee injection on skeletal muscle metabolism and contractile force in rats

OBJECTIVE

We tested the hypothesis that intrusion of the knee joint capsule alters quadriceps muscle metabolism and function independently from the damage induced to knee cartilage.

METHODS

Adult rats were separated into four groups: intraarticular injections of saline (SAL; n=9); intraarticular injections of papain, a model for osteoarthritis (PIA; n=7); sham injections (SHAM; n=8); and controls (CTL; n=5). 31P magnetic resonance spectroscopy (31P-MRS) was performed after 2 weeks. Spectra were obtained from the left quadriceps: two at baseline, eight during electrical stimulation with simultaneous measurement of contractile force, and 15 during recovery. 31P-MRS data were presented as the ratio of inorganic phosphate (Pi) to phosphocreatine (PCr), concentrations of PCr [PCr], intramuscular pH, and the rates and time constants of PCr breakdown during stimulation and PCr recovery. Intramuscular cytokine concentrations were measured within the quadriceps. Histologic slides of the knees were scored for severity of cartilage damage.

RESULTS

The interventional groups produced values of Pi/PCr ratio, [PCr], contractile force and pH that were significantly different from CTL. These changes in muscle function were accompanied by higher concentrations of interleukin-1 observed with PIA and SAL. We did not observe any effect of cartilage damage on muscle function or metabolism.

CONCLUSIONS

Knee joint intrusion alters quadriceps muscle metabolism with accelerated depletion of energy stores and fatigue during stimulation. This study demonstrates that needle intrusion into the knee joint results in muscle dysfunction, independently from the extent of cartilage damage.

Antinociceptive efficacy of lacosamide in the monosodium iodoacetate rat model for osteoarthritis pain

The etiology of osteoarthritis is multifactorial, with inflammatory, metabolic, and mechanical causes. Pain in osteoarthritis is initiated by mild intra-articular inflammation and degeneration of articular cartilage and subchondral bone. The principle of treatment with acetaminophen or non-steroidal anti-inflammatory drugs is to reduce pain and improve joint function. Recently, animal models for osteoarthritic pain behavior have been established. The most frequently used rat model for analyzing properties of drugs on the pathology of osteoarthritis is the injection of the metabolic inhibitor monosodium iodoacetate into the joint, which inhibits the activity of glyceraldehyde-3-phosphate dehydrogenase in chondrocytes. Here, we characterize the effect on pain behavior of lacosamide, a member of a family of functionalized amino acids that are analogues of endogenous amino acids and D-serine, in the monosodium iodoacetate rat model for osteoarthritis in comparison to diclofenac and morphine. Lacosamide (3, 10, and 30 mg/kg) was able to reduce secondary mechanical allodynia and hyperalgesia similarly to morphine (3 mg/kg). In contrast, diclofenac (30 mg/kg) was only effective in reducing secondary mechanical hyperalgesia. During the first week, pain is induced mainly by inflammation in the iodoacetate model, but afterwards inflammation plays only a minor role in pain. Lacosamide was able to inhibit pain at days 3, 7 and 14 after induction of arthritis. This shows that lacosamide is able to reduce pain behavior induced by multiple mechanisms in animals.

[Research advance on relation between humic acid and chondrocyte injuries]

Kashin-Beck disease (KBD) is a chronic osteoarthritic disease, and a endemic in parts of China, its etiology is unknown. Humic substance in drinking water has been proposed as one of the causative factors of KBD. At present, many studies on humic acid and chondrocyte injuries were reported. In this article, the progress of humic acid and chondrocyte injuries were reviewed.

Basic calcium phosphate crystals activate c-fos expression through a Ras/ERK dependent signaling mechanism

Diseases caused by calcium pyrophosphate dihydrate (CPPD) and basic calcium phosphate (BCP) crystals occur frequently in osteoarthritic joints. Both crystals induce mitogenesis, metalloproteinase synthesis and secretion by fibroblasts and chondrocytes, promoting degradation of articular tissue. We investigated the mechanism by which BCP activates the c-fos proto-oncogene, which has been shown to activate various matrix metalloproteinases (MMPs). We demonstrate that BCP crystals induce c-fos expression primarily through a Ras/ERK-dependent signaling mechanism targeting two highly conserved regulatory binding sites, the serum response element (SRE) and the cAMP response element (CRE). These results establish a calcium crystal induced, calcium/calmodulin independent, signaling pathway in which BCP crystals activate Ras/MAPK, which can directly target an SRF-containing transcription factor complex, to induce fibroblasts to secrete metalloproteinases.

Validation of a chemical osteoarthritis model in rabbit temporomandibular joint: a compliment to biomechanical models

To explore degenerative mechanisms occurring in the temporomandibular joint (TMJ), a chemical model of knee joint osteoarthritis using sodium mono-iodoacetate injection was transposed to the TMJ. Twelve New Zealand rabbits were used to document the effect of this drug on the TMJ. Eight rabbits underwent bilateral iodoacetate injection in the disco-condylar compartment while 4 served as controls. Rabbits were sacrificed at 10, 20, 30 and 40 days and joints studied by histology. Severity of the damage was time dependent and the use of iodoacetate allowed the observation, within a few weeks, of every osteoarthritic stage usually described in the literature. This study showed that the TMJ has a specific response to the degenerative process. This response was characterized by (i) thickening and fibrillation of the cartilage at the periphery of the lesion, tending to reduce mechanical stress in the lesional area and (ii) chondrocyte migration under areas where subchondral bone surface was locally destroyed. The extracellular matrix containing chondrocyte clusters and prechondrocytes dived around the bony defect and proceeded below the necrotic bone to promote the eviction of bony fragments into the joint cavity, pushing them up while the thickness of chondrocyte rows increased below. This could be interpreted as a repairing attempt due to the specific potential of fibrocartilage proliferative cells.

Prostacyclin antagonism reduces pain and inflammation in rodent models of hyperalgesia and chronic arthritis

The inhibition of prostaglandin (PG) synthesis is at the center of current anti-inflammatory therapies. Because cyclooxygenase-2 (COX-2) inhibitors and nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit the formation of multiple PGs, there is currently a strong focus on characterizing the role of the different PGs in the inflammation process and development of arthritis. Evidence to date suggests that both PGE(2) and PGI(2) act as mediators of pain and inflammation. Most of the data indicating a role for PGI(2) in this context have been generated in animal models of acute pain. Herein, we describe the role of PGI(2) in models of osteoarthritis (OA) and rheumatoid arthritis using a highly selective PGI(2) receptor (IP, Ptgir) antagonist and IP receptor-deficient mice. In the rat OA model using monoiodoacetate injection into the knee joint, the IP antagonist reduced pain with an efficacy approaching that of the NSAID diclofenac. In a chronic model of inflammatory arthritis, collagen-antibody induced arthritis model in mice, IP receptor-deficient mice displayed a 91% reduction in arthritis score. Interestingly, pretreatment with the IP [N-[4-(imidazolidin-2-ylideneamino)-benzyl]-4-methoxy-benzamide] antagonist in this model also caused a significant reduction of the symptoms, whereas administration of the compound after the initiation of arthritis had no detectable effect. Our data indicate that, in addition to its role in acute inflammation, PGI(2) is involved in the development of chronic inflammation. The results also suggest that the inhibition of PGI(2) synthesis by NSAIDs and COX-2 inhibitors, in addition to that of PGE(2), contributes to their efficacy in treating the signs of arthritis.

Development of N-2,4-pyrimidine-N-phenyl-N'-alkyl ureas as orally active inhibitors of tumor necrosis factor alpha (TNF-alpha) synthesis. Part 2

A new class of tumor necrosis factor alpha (TNF-alpha) synthesis inhibitors based on a N-2,4-pyrimidine-N-phenyl-N'-alkyl urea scaffold is described. Many of these compounds showed low-nanomolar activity against lipopolysaccharide stimulated TNF-alpha production. Two analogs were tested in an in vivo rat iodoacetate model of osteoarthritis and shown to be orally efficacious. X-ray co-crystallization studies with mutated p38alpha showed that these trisubstituted ureas interact with the ATP-binding pocket in a pseudo-bicyclic conformation brought about by the presence of an intramolecular hydrogen bonding interaction.

Comparison of the pharmacology of hydroxamate- and carboxylate-based matrix metalloproteinase inhibitors (MMPIs) for the treatment of osteoarthritis

OBJECTIVE AND DESIGN

Hydroxamic-and carboxylic-acid based matrix metalloproteinase inhibitors (MMPIs) were compared for their potency against various MMPs, pharmacodynamic properties and in vivo efficacy in a model of cartilage degeneration.

MATERIALS AND METHODS

The MMPIs were evaluated for their ability to inhibit human MMPs using the quenched fluorescence assay. The ability of the MMPIs to inhibit the degeneration of the knee joint was evaluated in rats injected intraarticularly with iodoacetate. The amount of MMPI in the plasma and cartilage was determined using liquid chromatography/mass spectrometry/mass spectrometry (LC/ MS/MS). Plasma protein binding was measured by ultrafiltration and unbound MMPI was quantitated using HPLC.

RESULTS

The hydroxamic acid based inhibitor PGE-3321996 and the carboxylic acids PGE-2909492 and PGE-6292544 were potent MMP-13 inhibitors, but only the hydroxamic acid PGE 3321996 demonstrated significant inhibition of knee degeneration in the rat iodoacetate model. Both of the carboxylic acids demonstrated superior pharmacokinetic properties and established much higher plasma concentrations than the hydroxamic acid. However, neither of the carboxylic acids was detectable in the cartilage, whereas, the hydroxamic acid was present in both the cartilage and the plasma. The carboxylic acid based MMPIs also demonstrated higher plasma protein binding (>99%) than the hydroxamic acid (79%).

CONCLUSIONS

Carboxylic acid-based MMPIs were identified that had superior in vivo plasma exposure compared to a hydroxamic acid inhibitor but lacked in vivo efficacy in the rat iodoacetate model of cartilage degeneration. The lack of in vivo efficacy of the carboxylic acid based MMPIs were probably due to their lack of cartilage penetration which was related to their physicochemical properties.

[Impact on the model of rat osteoarthritis of jingu tablet]

OBJECTIVE

To observe the influence of Jingu tablet (JGT) on the development and repair of osteoarthritis (OA).

METHOD

The admixture of 4% papain and 0.3 mol x L(-1) cysteine was injected into the rat's knee joint to make the model of rat OA, and distilled water, Gucining Capsule and JGT was given ig simultaneously to treat for 4 weeks in succession, and then animals were killed to measure every index.

RESULT

JGT could obviously improve the scope of activities of knee joint. There were significant differences between every dosage group and model group. In every dosage group, JGT could suppress the swelling of thickness of slippery membrane of joint, alleviate the inflammation symptoms of OA and obviouslical improve the pathologicol changes of slippery membrane and cartilage. JGT could also obviously reduce the content of MDA of slippery membrane and lighten the degree of cell damage.

CONCLUSION

JGT can lighten the retrograde affection of joint cartilage, obviously suppress the slippery membrane's inflammation and alleviate the scathing degree of cell. Therefore JGT has definite remedial effect to OA.

Osteoarticular side effects of BCG therapy

Although osteoarticular side effects of the Bacillus Calmette-Guérin (BCG) are rare compared to the number of administrations, BCG vaccination and cancer therapy are so widely used that the absolute number of cases is not negligible. Osteoarticular infection is an exceedingly rare complication of vaccination with the BCG. Intravesical BCG instillations used to treat superficial bladder cancer may cause arthralgia, reactive arthritis or osteoarticular infections. Intradermal BCG therapy used to treat a number of malignancies can cause osteoarticular infections or bilateral symmetric polyarthritis predominating in the wrists and fingers. In practice, when intravesical BCG instillation is followed by arthritis, hyperthermia is unhelpful for distinguishing septic arthritis from reactive arthritis. Arguments pointing to reactive arthritis include oligo- or polyarticular involvement and onset a few weeks (as opposed to a few months) after the last instillation. Nevertheless, joint fluid examination is in order to rule out septic arthritis. BCG-induced reactive arthritis usually responds well to nonsteroidal anti-inflammatory drugs. Osteoarticular infections related to BCG therapy should be treated by rifampin, isoniazid and ethambutol for 2 months, followed by rifampin and isoniazid for 10 months.

Effects of Aralia continentalis on hyperalgesia with peripheral inflammation

This study aimed to determine the antinociceptive effect of Aralia continentalis extract (AC) on Freund's adjuvant-induced arthritis in rats. Adult Sprague-Dawley rats received an injection of complete Freund's adjuvant (CFA) into the articular cavity of the ankle joint, and then antinociceptive behaviors and spinal Fos expression were examined. AC was found to suppress significantly nociceptive behaviors caused by CFA injection. In addition, it also decreased adjuvant-induced Fos expression in the lumbar spinal cord induced by CFA. In conclusion, this study showed that AC produced significant antinociceptive effects on CFA-induced arthritis in rats, and it is suggested that AC is recommended to alleviate the arthritis-related symptoms in humans.

Monitoring osteoarthritis in the rat model using optical coherence tomography

OBJECTIVE

A need exists for an animal model to assess therapeutics for osteoarthritis (OA) without sacrificing the animal. Our goal is to assess the progression of experimentally induced osteoarthritis in the rat knee joint by monitoring articular cartilage thickness, surface abnormalities, and collagen organization using a new technology known as optical coherence tomography (OCT).

DESIGN

OA was generated in Wistar Hanover rats via injection of sodium iodoacetate into the left articular joint of the knee while normal saline was injected as a control in the contralateral right knee. Rats were sacrificed at 1-, 2-, 3-, 4-, and 8-week intervals and the knee joints were subsequently harvested and imaged using normal and polarization sensitive OCT (PS-OCT). Treated knees were compared to normal counterparts in the contralateral leg. Following imaging, knees underwent both routine histological processing and picrosirus staining for organized collagen.

RESULTS

OCT images indicate that injection of sodium iodoacetate resulted in a progressive decrease in cartilage thickness and loss of the bone-cartilage interface which correlated with histology. In addition, PS-OCT was able to detect collagen disorganization, an early indicator of OA.

CONCLUSIONS

The use of OCT in combination with the induction of OA in rats is a promising new animal model for assessing articular changes with the goal of monitoring therapeutics longitudinally. Future work will extend the model to in vivo assessments.