Combined chondroitin sulfate and glucosamine for painful knee osteoarthritis: a multicentre, randomised, double-blind, non-inferiority trial versus celecoxib

Active viscosupplements for osteoarthritis treatment

OBJECTIVE

Osteoarthritis is a chronic, painful and disabling disease which prevalence is increasing in developing countries. Patients with osteoarthritis present a reduced synovial fluid viscoelasticity due to a reduction in concentration and molecular weight of hyaluronic acid. Currently, the main treatment used to restore the compromised rheological properties of synovial fluid is the viscosupplementation by hyaluronic acid injections that can be combined with oral anti-inflammatory drugs for pain relief. Combination of viscosupplements with chemical agents or drugs is emerging as a new strategy to provide a double action of synovial fluid viscoelasticity recovery and the therapeutic effect of the bioactive principle.

METHODS

In this review, we present the latest research on the combination of viscosupplements with active molecules. We conducted a literature review of articles published in different web search engines and categorized according to the active molecule introduced into the viscosupplement.

RESULTS

Generally, the introduction of anti-inflammatory molecules have shown to improve pain relief although some cytotoxicity has been demonstrated especially for non-steroidal anti-inflammatory drugs. Other molecules such as antioxidant or disease modifying osteoarthritis drugs have been reported to improve viscosupplementation action. Drug delivery systems combined with hyaluronic acid could enhance the activity of the encapsulated molecules and provide better control over the drug release. Finally, biological approaches such as the use of stem cells or platelet-rich plasma seem to be the most promising strategies for cartilage recovery.

CONCLUSIONS

Combination therapy of viscosupplements with therapeutic agents, drug delivery systems or regenerative therapies can improve viscosupplementation outcome in terms of pain relief and joint functionality. However, further research is needed in order to reach more conclusive results.

Long non-coding RNA activated by transforming growth factor beta alleviates lipopolysaccharide-induced inflammatory injury via regulating microRNA-223 in ATDC5 cells

Osteoarthritis (OA) is a conversant joint disease, which seriously threatens the health of the elderly, and even leads to disability. Long non-coding RNA-activated by transforming growth factor beta (lncRNA-ATB) has been reported in diverse cancers. However, the functions of lncRNA-ATB in OA remain uninvestigated. The current study aimed to explore the impacts of lncRNA-ATB on lipopolysaccharide (LPS)-induced inflammatory injury in ATDC5 cells and to uncover the underlying mechanism. LPS-induced ATDC5 cell injury model was constructed, and the effects of lncRNA-ATB on LPS-injured cells were explored via analyzing cell viability, apoptosis, iNOS, COX-2, and inflammatory cytokines (IL-6 and TNF-α). Subsequently, the relationship between lncRNA-ATB and microRNA (miR)-223 was detected, and whether miR-223 was involved in modulating LPS-induced cells injury in ATDC5 cells was investigated. Finally, MyD88/NF-κB and p38MAPK pathways were assessed to explore the underlying mechanism. Results showed that LPS repressed cell viability, induced apoptosis, and promoted iNOS, COX-2, IL-6 and TNF-α expression. Additionally, we observed that lncRNA-ATB expression was down-regulated in LPS-injured cells, and lncRNA-ATB overexpression significantly alleviated LPS-induced inflammatory injury in ATDC5 cells. Interesting results revealed that miR-223 expression was down-regulated by lncRNA-ATB and miR-223 overexpression declined the protective effect of lncRNA-ATB on LPS-injured ATDC5 cells. Further, the signaling pathway experiments showed that lncRNA-ATB inhibited MyD88/NF-κB and p38MAPK pathways by down-regulating miR-223 in LPS-injured cells. These data demonstrated that lncRNA-ATB protected ATDC5 cells against LPS-induced inflammatory injury by repressing MyD88/NF-κB and p38MAPK pathways, which was mediated by down-regulation of miR-223.

In situ fabrication of a composite hydrogel with tunable mechanical properties for cartilage tissue engineering

A composite hydrogel with tunable mechanical properties has been fabricated and characterized in this study.

Multicenter, randomized, double-blind clinical trial to evaluate efficacy and safety of combined glucosamine sulfate and chondroitin sulfate capsules for treating knee osteoarthritis

OBJECTIVES

To compare the efficacy and safety of a new fixed dose combination of glucosamine sulfate and chondroitin sulfate capsules (GS/CS) versus the fixed dose combination of glucosamine hydrochloride and chondroitin sulfate (Cosamin DS®) in capsules in patients with osteoarthritis (OA) of the knee.

METHODS

Multicenter, randomized, double-blind study. Participants with knee OA Kellgren-Lawrence grades 1 to 3 and VAS of symptoms ≥4 cm were randomized to receive GS/CS or Cosamin DS® over 12 weeks. The primary efficacy endpoint was the evaluation of the analgesic efficacy by the investigator. Secondary efficacy endpoints included: joint pain and swelling, investigator efficacy of the medication, and the use of rescue medication. Adverse events and drug tolerability were analyzed.

RESULTS

One hundred patients were randomized, and 50 patients were allocated to each group. The analgesic efficacy evaluated by the investigator in the GS/CS group was 88.9, 95%CI: 75.2, 95.8% and in the Cosamin DS® group was 85.4%; 95%CI: 70.1, 93.4%. The mean reduction in the pain intensity was significant in both groups (p < 0.001), with no difference between them. The primary efficacy analysis demonstrated the non-inferiority of the GS/CS group compared with the Cosamin DS® group; the lower limit of the 90% confidence interval (CI) between the two groups (- 8.39%) was higher than the established margin of non-inferiority of - 10.00%. Improvement in other efficacy outcomes was observed, again without differences between groups. Adverse events were similar between groups and both presented good tolerability.

CONCLUSIONS

The new fixed-dose formulation of GS/CS is effective in treating knee OA, presenting a good safety and tolerability profile.

TRIAL REGISTRATION

( https://clinicaltrials.gov/ct2/show/NCT00955552?term=NCT00955552&rank=1 ; ClinicalTrials.gov ; register number NCT00955552; First randomized patient: 08/17/2010).

Effect of glucosamine and chondroitin sulfate in symptomatic knee osteoarthritis: a systematic review and meta-analysis of randomized placebo-controlled trials

Although glucosamine and chondroitin sulfate have showed beneficial effects on joint tissues in osteoarthritis (OA), their therapeutic use in the clinical setting is still debatable. Hence, a systematic review and meta-analysis of randomized placebo-controlled trials was conducted to investigate the efficacy of glucosamine and chondroitin sulfate on knee OA symptoms. Medline, SCOPUS, Web of Science, and Google Scholar databases were searched for randomized placebo-controlled trials evaluating the effect of orally administered glucosamine and/or chondroitin sulfate on OA symptoms using the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) and/or the Visual Analog Scale (VAS). Meta-analysis was conducted using a random-effects model and generic inverse-variance method. Heterogeneity was tested using the I2 statistic index. Treatments with glucosamine and chondroitin were found to significantly reduce pain in VAS [weighted mean difference (WMD) - 7.41 mm, 95% CI - 14.31, - 0.51, p = 0.04 and WMD - 8.35 mm, 95% CI - 11.84, - 4.85, p < 0.00001, respectively]. Their combination did not show this behavior (WMD - 0.28 mm, 95% CI - 8.87, 8.32, p = 0.95). None of the glucosamine, chondroitin or their combination had a significant positive effect on the total WOMAC index and its subscores. Oral supplementation with glucosamine or chondroitin sulfate reduces pain in knee OA. However, there is no additional effect using both therapeutic agents in combination for the management of symptomatic knee OA.

α-Lipoic Acid Potentiates the Anti-Inflammatory Activity of Avocado/Soybean Unsaponifiables in Chondrocyte Cultures

Objective Pro-inflammatory mediators such as prostaglandin E-2 (PGE₂) play major roles in the pathogenesis of osteoarthritis (OA). Although current pharmacologic treatments reduce inflammation, their prolonged use is associated with deleterious side effects prompting the search for safer and effective alternative strategies. The present study evaluated whether chondrocyte production of PGE₂ can be suppressed by the combination of avocado/soybean unsaponifiables (ASU) and α-lipoic acid (LA). Design Chondrocytes from articular cartilage of equine joints were incubated for 24 hours with: (1) control media, (2) ASU, (3) LA, or (4) ASU + LA combination. Cells were activated with lipopolysaccharide (LPS), interleukin 1β (IL-1β) or hydrogen peroxide (H₂O₂) for 24 hours and supernatants were immunoassayed for PGE₂. Nuclear factor-kappa B (NF-κB) analyses were performed by immunocytochemistry and Western blot following 1 hour of activation with IL-1β. Results LPS, IL-1β, or H₂O₂ significantly increased PGE₂ production. ASU or LA alone suppressed PGE₂ production in LPS and IL-1β activated cells. Only LA alone at 2.5 µg/mL was inhibitory in H₂O₂-activated chondrocytes. ASU + LA inhibited more than either agent alone in all activated cells. ASU + LA also inhibited the IL-1β induced nuclear translocation of NF-κB. Conclusions The present study provides evidence that chondrocyte PGE₂ production can be inhibited by the combination of ASU + LA more effectively than either ASU or LA alone. Inhibition of PGE₂ production is associated with the suppression of NF-κB translocation. The potent inhibitory effect of ASU + LA on PGE₂ production could offer a potential advantage for a combination anti-inflammatory/antioxidant approach in the management of OA.

Glucosamine and Chondroitin Sulfate: What Has Been Learned Since the Glucosamine/chondroitin Arthritis Intervention Trial

Glucosamine and chondroitin sulfate, alone or in combination, are used worldwide by individuals suffering from osteoarthritis pain. They are by prescription in some countries but are available as over-the-counter dietary supplements in other countries, such as the United States. The inconclusive results of the National Institutes of Health-sponsored Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) did little to clarify the efficacy of these agents. However, some newer studies have provided a better perspective on the potential benefits that they can offer. Because the 2 in combination showed a significant level of efficacy in the moderate-to-severe knee osteoarthritis subgroup of the GAIT, this review examines the randomized, controlled trials published from that time to the present. The findings of these studies are mixed, owing in some cases to the high rate of placebo response added to by the ethical incorporation of rescue analgesics into protocols designed to evaluate the slow-acting, subtle effects of glucosamine and chondroitin sulfate in combination. The strong influence of the placebo effect and confounding of results by rescue analgesics point to the importance of objective measurement tools such as osteoarthritis biomarker panels in long-term glucosamine/chondroitin sulfate clinical trials with less reliance on the subjective measurement tools commonly used in osteoarthritis trials of pharmaceuticals. [Orthopedics. 2018; 41(4):200-207.].

Evaluation of the novel avocado/soybean unsaponifiable Arthrocen to alter joint pain and inflammation in a rat model of osteoarthritis

BACKGROUND

Avocado/soybean unsaponifiables such as Arthrocen have been reported to reduce cartilage catabolism and chondrocytic synthesis of inflammatory mediators associated with osteoarthritis (OA). While there is some clinical evidence that avocado/soybean unsaponifiables can reduce OA pain, no preclinical studies have corroborated this observation. The present study determined whether addition of an avocado/soybean unsaponifiable (Arthrocen) to the drinking water of OA rats reduced direct and referred joint pain.

METHODS

OA was induced in male Wistar rats by intra-articular injection of sodium monoiodoacetate (MIA: 0.3mg) and animals were allowed to recover for 14 days. Arthrocen was added to the drinking water which was available to animals ad libitum. On day 30, joint pain was assessed by dynamic incapacitance while referred pain was determined by von Frey hair algesiometry.

RESULTS

The joint damage induced by MIA injection was severe and was consistent with end-stage OA. Arthrocen consumption (approximately 35 mg/day) attenuated the joint oedema associated with MIA injection. Hindlimb weight bearing also significantly improved in Arthrocen-treated rats (P<0.05); however, von Frey hair mechanosensitivity was unaffected by this treatment.

CONCLUSIONS

These data indicate that Arthrocen has the potential to reduce joint inflammation and pain associated with end-stage OA.

A Traditional Herbal Formula Xianlinggubao for Pain Control and Function Improvement in Patients with Knee and Hand Osteoarthritis: A Multicenter, Randomized, Open-Label, Controlled Trial

Evidence of efficacy of a traditional herbal formula Xianlinggubao (XLGB) for treatment of osteoarthritis (OA) is limited. The present study was designed to evaluate the efficacy of XLGB in the management of patients with knee and hand OA. This was a multicenter, stratified, open-label, randomized controlled trial conducted at six centers in China. People aged 40 or above, diagnosed with OA of the knee or hand, were randomly assigned to the XLGB treatment group or watchful waiting control group. Main outcome measures were the changes in the numeric pain rating scales (NPRS) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) or the Australian/Canadian Osteoarthritis Hand Index (AUSCAN) scores, from baseline to 6 months. In total 534 patients (272 to XLGB and 262 to control group) received interventions. Participants in the XLGB group exhibited significant improvement in NPRS (P < 0.001) and WOMAC score (P < 0.001) or AUSCAN score (P < 0.001) compared to control group. Treatment with XLGB at current regime significantly reduced pain and improved function of the knee and hand in patients with OA over a 6-month period, implying that XLGB could be suggested as an alternative treatment for patients with knee or hand OA.

Metabolic engineering of carbon overflow metabolism of Bacillus subtilis for improved N-acetyl-glucosamine production

Bacillus subtilis is widely used as cell factories for the production of important industrial biochemicals. Although many studies have demonstrated the effects of organic acidic byproducts, such as acetate, on microbial fermentation, little is known about the effects of blocking the neutral byproduct overflow, such as acetoin, on bioproduction. In this study, we focused on the influences of modulating overflow metabolism on the production of N-acetyl-d-glucosamine (GlcNAc) in engineered B. subtilis. We found that acetoin overflow competes with GlcNAc production, and blocking acetoin overflow increased GlcNAc titer and yield by 1.38- and 1.39-fold, reaching 48.9 g/L and 0.32 g GlcNAc/g glucose, respectively. Further blocking acetate overflow inhibited cell growth and GlcNAc production may be induced by inhibiting glucose uptake. Taken together, our results show that blocking acetoin overflow is a promising strategy for enhancing GlcNAc production. The strategies developed in this work may be useful for engineering strains of B. subtilis for producing other important biochemicals.

Possible role of chondroitin sulphate and glucosamine for primary prevention of colorectal cancer. Results from the MCC-Spain study

A safe and effective colorectal cancer (CRC) chemoprevention agent remains to be discovered. We aim to evaluate the association between the use of glucosamine and/or chondroitin sulphate and risk of colorectal cancer (CRC) in the MCC-Spain study, a case-control study performed in Spain that included 2140 cases of CRC and 3950 population controls. Subjects were interviewed on sociodemographic factors, lifestyle, family and medical history and regular drug use. Adjusted odds ratios and their 95% confidence intervals were estimated. The reported frequency of chondroitin and/or glucosamine use was 2.03% in controls and 0.89% in cases. Users had a reduced risk of CRC (OR: 0.47; 95% CI: 0.28–0.79), but it was no longer significant when adjusted for NSAID (nonsteroidal anti-inflammatory drugs) use (OR: 0.82; 95% CI: 0.47–1.40). A meta-analysis with previous studies suggested a protective effect, overall and stratified by NSAID use (OR: 0.77; 95% CI: 0.62–0.97). We have not found strong evidence of an independent preventive effect of CG on CRC in our population because the observed effects of our study could be attributed to NSAIDs concurrent use. These results merit further research due to the safety profile of these drugs.

Clinical Considerations for the Use Lower Extremity Arthroplasty in the Elderly

There is an increase in the aging population that has led to a surge of reported cases of osteoarthritis and a greater demand for lower extremity arthroplasty. This article aims to review the current treatment options and expectations when considering lower extremity arthroplasty in the elderly patient with an emphasis on the following subjects: (1) updated clinical guidelines for the management of osteoarthritis in the lower extremity, (2) comorbidities and risk factors in the surgical patient, (3) preoperative evaluation and optimization of the surgical patient, (4) surgical approach and implant selection, and (5) rehabilitation and life after lower extremity arthroplasty.

Regenerative approaches for cartilage repair in the treatment of osteoarthritis

Osteoarthritis (OA) as a debilitating affliction of joints currently affects millions of people and remains an unsolved problem. The disease involves multiple cellular and molecular pathways that converge on the progressive destruction of cartilage. Activation of cartilage regenerative potential and specific targeting pathogenic mediators have been the major focus of research efforts aimed at slowing the progression of cartilage degeneration and preserve joint function. This review will summarize recent key discoveries toward better understanding of the complex mechanisms behind OA development and highlight the latest advances in basic and clinical research in the approach for cartilage regeneration. Prospectively, more potent therapeutic strategies against progressive cartilage deterioration may use a combination of cytotherapy, pharmacotherapy, and bioscaffoldings for improved chondrogenic differentiation and stem/progenitor cell homing as well as the concomitant reduced enzymatic matrix degradation and inflammation. Further, treatments need to be provided with increased preciseness of targeted therapy. One might expect that the regenerative therapies could potentially control or even possibly cure OA if performed at early stages of the disease.

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.

Levels of serum biomarkers from a two-year multicentre trial are associated with treatment response on knee osteoarthritis cartilage loss as assessed by magnetic resonance imaging: an exploratory study

Background

There is an obvious need to identify biomarkers that could predict patient response to an osteoarthritis (OA) treatment. This post hoc study explored in a 2-year randomized controlled trial in patients with knee OA, the likelihood of some serum biomarkers to be associated with a better response to chondroitin sulfate in reducing cartilage volume loss.

Methods

Eight biomarkers were studied: hyaluronic acid (HA), C reactive protein (CRP), adipsin, leptin, N-terminal propeptide of collagen IIα (PIIANP), C-terminal crosslinked telopeptide of type I collagen (CTX-1), matrix metalloproteinase-1 (MMP-1), and MMP-3. Patients were treated with chondroitin sulfate (1200 mg/day; n = 57) or celecoxib (200 mg/day; n = 62). Serum biomarkers were measured at baseline. The cartilage volume at baseline and its loss at 2 years were assessed by quantitative magnetic resonance imaging (MRI). Statistical analysis included analysis of covariance.

Results

As data from the original MOSAIC trial showed no differences in cartilage volume and loss in the lateral compartment of the knee joint between the two treatment groups in any comparison, only the medial compartment and its subregions were studied. Stratification according to the median biomarker levels was used to discriminate treatment effect. In patients with levels of biomarkers of inflammation (HA, leptin and adipsin) lower than the median, those treated with chondroitin sulfate demonstrated less cartilage volume loss in the medial compartment, condyle, and plateau (p ≤ 0.047). In contrast, patients treated with chondroitin sulfate with higher levels of MMP-1 and MMP-3, biomarkers of cartilage catabolism, had less cartilage volume loss in the medial compartment, condyle, and plateau (p ≤ 0.050). Patients with higher levels of PIIANP and CTX-1, biomarkers related to collagen anabolism and bone catabolism, respectively, had reduced cartilage volume loss in the medial condyle (p ≤ 0.026) in the chondroitin sulfate group.

Conclusion

This study is suggestive of a potentially greater response to chondroitin sulfate treatment on cartilage volume loss in patients with knee OA with low level of inflammation and/or greater level of cartilage catabolism.

Trial registration

This is a post hoc study. Original trial registration: ClinicalTrials.gov, NCT01354145. Registered on 13 May 2011. 

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1377-y) contains supplementary material, which is available to authorized users.

[Treatment satisfaction in primary care patients with osteoarthrosis.]

OBJECTIVE

As in other chronic problems, the approach of the patient with osteoarthritis tends to a shared decision-making model, in which the patient's point of view must be considered in the choice of treatment. The objetive was to evaluate treatment satisfaction in patients with osteoarthritis and to verify if there are differences between different pharmacological options, as well as to determine if there is any association with functional status and clinical and sociodemographic characteristics.

METHODS

A cross-sectional observational study was conducted in a sample of 487 patients selected by consecutive sampling. The main variable was the level of satisfaction with the treatment (ARTS questionnaire). The functional status of the patients was assessed using the WOMAC scale. Other variables considered were: treatment characteristics, therapeutic adherence, adverse events, and clinical and sociodemographic variables.

RESULTS

In the ARTS questionnaire the patients, in a range between 28 and 87, obtained an average score of 65.3 (SD: 9.9). The score was not significantly different in consumers of 1, 2 or more drugs. Among those who consumed only one drug, there were no differences between the different drug types. In the functional state, an average score of 30.2 points (SD: 20.8) was obtained and a weak negative correlation was observed with the level of satisfaction (r = -0.252; p=0.001). Multiple linear regression showed a higher score on the ARTS scale (p=0.05) in patients with lower WOMAC score, older age and absence of adverse events.

CONCLUSIONS

In patients with osteoarthritis, a moderate level of satisfaction with pharmacological treatment is observed, conditioned by their functional status, their sociodemographic characteristics and the presence of adverse events. In general, satisfaction does not depend on either the characteristics of the treatment or the number of drugs consumed.

Intramuscular clodronate in erosive osteoarthritis of the hand is effective on pain and reduces serum COMP: a randomized pilot trial-The ER.O.D.E. study (ERosive Osteoarthritis and Disodium-clodronate Evaluation)

We evaluated the efficacy and safety of intramuscular clodronate (CLO) for the treatment of active erosive osteoarthritis of the hand (EOA). Forty outpatients treated with anti-inflammatory (NSAIDs) or analgesic drugs since at least 6 months, for at least 3 days a week, were randomly divided into two groups. Group A: 24 patients treated for 6 months with intramuscular (i.m.) CLO added to usual NSAIDs or analgesic drugs. The attack dose was 200 mg/day i.m. for 10 days followed by a maintenance dose of CLO i.m. 200 mg/day for 6 days after 3 and 6 months. Group B: 16 patients who continued the usual treatment with anti-inflammatory or analgesic drugs. Patients in both groups reported in a diary, day by day, the consumption of symptomatic drugs. In group A, the consumption of anti-inflammatory or analgesic drugs (p < 0.0001), pain (p < 0.0001), number of tender joints (p = 0.0097), number of swollen joints (p = 0.0251), Dreiser score (p = 0.0119), and patient's and physician's global assessment of disease activity significantly decreased (both p < 0.001). At 6 months, serum COMP also significantly decreased (p < 0.0029). Strength of right (p = 0.0465) and left hand (+38%, p = ns) significantly increased. In group B, there was no significant change in all parameters considered. Intramuscular CLO in EOA of the hand is effective and safe on pain with a significant reduction in the consumption of anti-inflammatory or analgesic drugs, increasing the functionality of the hands. Serum COMP reduction suggests that CLO could play a role as a disease-modifying drug (EudraCT number 2013-000832-85).

Sulfation of Glycosaminoglycans and Its Implications in Human Health and Disorders

Sulfation is a dynamic and complex posttranslational modification process. It can occur at various positions within the glycosaminoglycan (GAG) backbone and modulates extracellular signals such as cell-cell and cell-matrix interactions; different sulfation patterns have been identified for the same organs and cells during their development. Because of their high specificity in relation to function, GAG sulfation patterns are referred to as the sulfation code. This review explores the role of GAG sulfation in different biological processes at the cell, tissue, and organism levels. We address the connection between the sulfation patterns of GAGs and several physiological processes and discuss the misregulation of GAG sulfation and its involvement in several genetic and metabolic disorders. Finally, we present the therapeutic potential of GAGs and their synthetic mimics in the biomedical field.

Chemical Isotope Labeling LC-MS for Monitoring Disease Progression and Treatment in Animal Models: Plasma Metabolomics Study of Osteoarthritis Rat Model

We report a chemical isotope labeling (CIL) liquid chromatography mass spectrometry (LC-MS) method generally applicable for tracking metabolomic changes from samples collected in an animal model for studying disease development and treatment. A rat model of surgically induced osteoarthritis (OA) was used as an example to illustrate the workflow and technical performance. Experimental duplicate analyses of 234 plasma samples were carried out using dansylation labeling LC-MS targeting the amine/phenol submetabolome. These samples composed of 39 groups (6 rats per group) were collected at multiple time points with sham operation, OA control group, and OA rats with treatment, separately, using glucosamine/Celecoxib and three traditional Chinese medicines (Epimedii folium, Chuanxiong Rhizoma and Bushen-Huoxue). In total, 3893 metabolites could be detected and 2923 of them were consistently detected in more than 50% of the runs. This high-coverage submetabolome dataset could be used to track OA progression and treatment. Many differentiating metabolites were found and 11 metabolites including 2-aminoadipic acid, saccharopine and GABA were selected as potential biomarkers of OA progression and OA treatment. This study illustrates that CIL LC-MS is a very useful technique for monitoring incremental metabolomic changes with high coverage and accuracy for studying disease progression and treatment in animal models.

Chondroitin sulphate inhibits NF-κB activity induced by interaction of pathogenic and damage associated molecules

OBJECTIVE

To evaluate the anti-inflammatory mechanism of action of Chondroitin Sulphate (CS).

DESIGN

THP-1 macrophages were cultured with a range of sizes and concentrations of HA fragments with TLR4 (LPS in a physiologically relevant concentration determined by analyses of sera of a community clinic ascertained knee osteoarthritis (OA) cohort) or TLR2 (heat killed listeria bacteria) agonists and varying concentrations of CS in a physiologically relevant range (10-200 μg/ml). We measured IL-1β release, intracellular IL-1β, proIL-1β, caspase-1 and NF-κB activity and DNA binding activity of NF-κB transcription factors from nuclear and cytoplasmic extracts.

RESULTS

Serum LPS was significantly associated with radiographic knee joint space narrowing (JSN) (P = 0.02) in the OA cohort (n = 40). The priming dose of LPS used for these experiments (10 ng/ml) was below the lowest serum concentration of the OA cohort (median 47.09, range 14.43-81.36 ng/ml). Priming doses of LPS and HA fragments alone did not elicit an inflammatory response. However, primed with LPS, HA fragments produced large dose-dependent increases in IL-1β that were inhibitable by CS. CS did not inhibit caspase-1 activity but in physiologically achievable concentrations, attenuated NF-κB activity induced by either the TLR4 (LPS 1000 ng/ml) or TLR2 agonists alone or in combination with HA fragments. LPS induced and CS significantly reduced activity of canonical NF-κB transcription factors, p65, p50, c-Rel and RelB.

CONCLUSIONS

Subinflammatory concentrations of pathogenic (LPS, listeria) and damage associated (HA) molecules interact to induce macrophage-related inflammation. CS works upstream of the inflammasome by inhibiting activation of NF-κB transcription factors.

The combined therapy with chondroitin sulfate plus glucosamine sulfate or chondroitin sulfate plus glucosamine hydrochloride does not improve joint damage in an experimental model of knee osteoarthritis in rabbits

Osteoarthritis is the most common chronic joint disorder especially during aging. Although with controversies, glucosamine, both in its forms of sulfate and hydrochloride, and chondroitin sulfate are commonly employed to treat osteoarthritis. Due to the modest improve in the symptoms observed in patients treated with these drugs alone, a formulation combining both agents has been considered. The discrepant results achieved for pain control or structural improvement in osteoarthritis patients has been attributed to the quality of chemical formulations or different bias in clinical studies. The current study has been designed to test the effects of two different combined formulations with adequate pharmaceutical grade of these drugs in osteoarthritic joints, and to explore the underlying mechanisms modulated by both formulations in different osteoarthritis target tissues. Knee osteoarthritis was surgically induced in experimental rabbits. Some animals received the combined therapy (CT)1, (chondroitin sulfate 1200mg/day + glucosamine sulfate 1500mg/day), or the CT2 ((chondroitin sulfate 1200mg/day + glucosamine hydrochloride 1500mg/day). Neither CT1 nor CT2 significantly modified the cartilage damage or the synovial inflammation observed in osteoarthritic animals. Treatments were also unable to modify the presence of pro-inflammatory mediators, and the synthesis of metalloproteinases in the cartilage or in the synovium of osteoarthritic animals. Combined therapies did not modify the decrease in the subchondral bone mineral density observed in osteoarthritic rabbits. Therapies of chondroitin sulfate plus glucosamine sulfate or chondroitin sulfate plus glucosamine hydrochloride failed to improve structural damage or to ameliorate the inflammatory profile of joint tissues during experimental osteoarthritis.

Chondroitin sulfate efficacy versus celecoxib on knee osteoarthritis structural changes using magnetic resonance imaging: a 2-year multicentre exploratory study

Background

In osteoarthritis (OA) treatment, although chondroitin sulfate (CS) was found in a number of studies using radiography to have a structure-modifying effect, to date CS use is still under debate. A clinical study using quantitative magnetic resonance imaging (qMRI) is therefore of the utmost importance. Here we report data from a 24-month, randomised, double-blind, double-dummy, controlled, comparative exploratory study of knee OA. The primary endpoint was to determine the effect of CS 1200 mg/day versus celecoxib 200 mg/day on cartilage volume loss (CVL) in the lateral compartment over time as measured by qMRI. Secondary endpoints included assessment of the OA structural changes and signs and symptoms of OA.

Methods

qMRI was performed at baseline and at 12 and 24 months. CVL, bone marrow lesion size, and synovial thickness were evaluated using qMRI. The primary statistical analysis was carried out on the modified intention-to-treat (mITT) population (n = 138) using chi-squared, Fisher’s exact, Wilcoxon Mann–Whitney, and Student’s t tests and analysis of covariance. Analyses were also conducted on the according-to-protocol (ATP; n = 120) population.

Results

In the adjusted mITT analysis, compared with celecoxib treatment, patients treated with CS had a significant reduced CVL at 24 months in the medial compartment (celecoxib –8.1 % ± 4.2, CS –6.3 % ± 3.2; p = 0.018) and medial condyle (–7.7 % ± 4.7, –5.5 % ± 3.9; p = 0.008); no significant effect was seen in the lateral compartment. In the ATP population, CS reduced CVL in the medial compartment at 12 months (celecoxib –5.6 % ± 3.0, CS –4.5 % ± 2.6; p = 0.049) and 24 months (celecoxib –8.4 % ± 4.2, CS –6.6 % ± 3.3; p = 0.021), and in the medial condyle at 24 months (celocoxib –8.1 % ± 4.7, CS –5.7 % ± 4.0; p = 0.010). A trend towards a statistically reduced synovial thickness (celecoxib +17.96 ± 33.73 mm, CS –0.66 ± 22.72 mm; p = 0.076) in the medial suprapatellar bursa was observed in CS patients. Both groups experienced a marked reduction in the incidence of patients with joint swelling/effusion and in symptoms over time. Data showed similar good safety profiles including cardiovascular adverse events for both drugs.

Conclusion

This study demonstrated, for the first time in a 2-year randomised controlled trial using qMRI, the superiority of CS over celecoxib at reducing CVL in knee OA patients.

Trial registration

ClinicalTrials.gov NCT01354145. Registered 13 May 2011.

Electronic supplementary material

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Osteoarthritis

Osteoarthritis (OA) is the most common joint disorder, is associated with an increasing socioeconomic impact owing to the ageing population and mainly affects the diarthrodial joints. Primary OA results from a combination of risk factors, with increasing age and obesity being the most prominent. The concept of the pathophysiology is still evolving, from being viewed as cartilage-limited to a multifactorial disease that affects the whole joint. An intricate relationship between local and systemic factors modulates its clinical and structural presentations, leading to a common final pathway of joint destruction. Pharmacological treatments are mostly related to relief of symptoms and there is no disease-modifying OA drug (that is, treatment that will reduce symptoms in addition to slowing or stopping the disease progression) yet approved by the regulatory agencies. Identifying phenotypes of patients will enable the detection of the disease in its early stages as well as distinguish individuals who are at higher risk of progression, which in turn could be used to guide clinical decision making and allow more effective and specific therapeutic interventions to be designed. This Primer is an update on the progress made in the field of OA epidemiology, quality of life, pathophysiological mechanisms, diagnosis, screening, prevention and disease management.

In Vivo Osteoinduction: Evaluating 2-Beta Coxatene as an Immunoinductive Compound and Novel Ingredient for Joint Support

CONTEXT

Osteoarthritis (OA) is a degenerative joint disease characterized by progressive loss of articular cartilage. Many treatments lack the ability to stimulate the growth of native cartilage tissue while they simultaneously increase joint comfort. For the past few decades, dietary supplements have been investigated for the ability to both address joint inflammation and stimulate cartilage tissue.

OBJECTIVES

The present study intended to examine the supplement's in vivo osteoinductive capabilities and clinical efficacy for overall joint health.

DESIGN

The research team designed a randomized, double-blind, comparative clinical trial.

SETTING

The study took place via telephone interviews.

PARTICIPANTS

Participants had self-reported OA of a weight-bearing joint (ie, of the knee, hip, spine, or ankle). Patients were recruited using the Health Science Institute, a consumer supplement newsletter.

INTERVENTION

Participants in the intervention group were blindly given 135 mg of 2-Beta Coxatene (2BCT) orally, which contained (1) a custom blend of low-dose Cyplexinol, an osteoinductive protein complex derived from bovine bone tissue, and (2) Boswellia serrata resin enriched to 65% 3-O-Acetyl-11-keto-β-Boswellic acid. A positive control group was blindly given 1500 mg of glucosamine hydrogen chloride and 1200 mg of chondroitin sulfate. Participants took the supplements for 3 mo.

OUTCOME MEASURES

A histological evaluation was performed on an athymic rat to test the supplement's in vivo osteoinductive capabilities. A negative control, commercially purchased, unhydrolyzed type 2 collagen was used for that test. Participants were evaluated for parameters of pain and joint function at baseline (day 0) and at days 7, 30, and 90 using the Western Ontario and McMaster Universities (WOMAC) OA index and a visual analogue scale (VAS).

RESULTS

The histological evaluation of the athymic rat confirmed that the Cyplexinol component of the 2BCT was positive for de novo bone tissue and collagen synthesis, corroborating osteoinduction. In the clinical trial, the intervention group reported significant decreases of 57.4%, 52.5%, and 58% in normalized WOMAC scores for pain, stiffness, and joint functionality, respectively, from baseline to postintervention. The control group reported a decrease of 17.5%, 18.1%, and 23.9% for pain, stiffness, and joint functionality, respectively. For the intervention group, pain intensity and frequency, as measured by the VAS, also decreased 57.1% and 56.3%, respectively, from baseline to postintervention, whereas the control group showed a decrease in VAS scores of 18.0% and 14.8%, respectively. In total, an average of 81.2% of participants administered the 2BCT had reported a statistically significant improvement from baseline to postintervention, compared with 22.9% of participants administered glucosamine and chondroitin.

CONCLUSIONS

In vivo studies confirmed that the bioactive proteins (Cyplexinol) within the 2BCT stimulated de novo bone and cartilage tissue production, demonstrating osteoinduction. The intervention group reported greater improvements in the psychometric evaluations that assessed joint comfort when compared with participants given the glucosamine and chondroitin. The results suggest that 2BCT may provide a novel and synergistic response to preserving joint homeostasis and improving quality of life.

Glucosamine exposure reduces proteoglycan synthesis in primary human endothelial cells in vitro

PURPOSE

Glucosamine (GlcN) supplements are promoted for medical reasons, for example, for patients with arthritis and other joint-related diseases. Oral intake of GlcN is followed by uptake in the intestine, transport in the circulation and thereafter delivery to chondrocytes. Here, it is postulated to have an effect on synthesis and turnover of extracellular matrix constituents expressed by these cells. Following uptake in the intestine, serum levels are transiently increased, and the endothelium is exposed to increased levels of GlcN. We investigated the possible effects of GlcN on synthesis of proteoglycans (PGs), an important matrix component, in primary human endothelial cells.

METHODS

Primary human endothelial cells were cultured in vitro in medium with 5 mM glucose and 0-10 mM GlcN. PGs were recovered and analysed by western blotting, or by SDS-PAGE, gel chromatography or ion-exchange chromatography of (35)S-PGs after (35)S-sulphate labelling of the cells.

RESULTS

The synthesis and secretion of (35)S-PGs from cultured endothelial cells were reduced in a dose- and time-dependent manner after exposure to GlcN. PGs are substituted with sulphated glycosaminoglycan (GAG) chains, vital for PG function. The reduction in (35)S-PGs was not related to an effect on GAG chain length, number or sulphation, but rather to the total expression of PGs.

CONCLUSION

Exposure of endothelial cells to GlcN leads to a general decrease in (35)S-PG synthesis. These results suggest that exposure to high levels of GlcN can lead to decreased matrix synthesis, contrary to what has been claimed by supporters of such supplements.

Non-operative management of osteoarthritis of the knee joint

Osteoarthritis is a chronic disorder of synovial joints in which there is progressive softening and disintegration of articular cartilage accompanied by the growth of osteophytes. Treatment designed for osteoarthritis should aim at reducing pain, improve joint mobility, and limit functional impairment. It can be achieved by pharmacological and non-pharmacological means. Non-operative treatment of OA is useful for patients with KL grade 1-3, which are early stages of OA. However, in an advanced stage of OA (KL grade 4), surgical treatment is needed as definitive treatment.

Non-surgical treatments for the management of early osteoarthritis

Non-surgical treatments are usually the first choice for the management of knee degeneration, especially in the early osteoarthritis (OA) phase when no clear lesions or combined abnormalities need to be addressed surgically. Early OA may be addressed by a wide range of non-surgical approaches, from non-pharmacological modalities to dietary supplements and pharmacological therapies, as well as physical therapies and novel biological minimally invasive procedures involving injections of various substances to obtain a clinical improvement and possibly a disease-modifying effect. Numerous pharmaceutical agents are able to provide clinical benefit, but no one has shown all the characteristic of an ideal treatment, and side effects have been reported at both systemic and local level. Patients and physicians should have realistic outcome goals in pharmacological treatment, which should be considered together with other conservative measures. Among these, exercise is an effective conservative approach, while physical therapies lack literature support. Even though a combination of these therapeutic options might be the most suitable strategy, there is a paucity of studies focusing on combining treatments, which is the most common clinical scenario. Further studies are needed to increase the limited evidence on non-surgical treatments and their combination, to optimize indications, application modalities, and results with particular focus on early OA. In fact, most of the available evidence regards established OA. Increased knowledge about degeneration mechanisms will help to better target the available treatments and develop new biological options, where preliminary results are promising, especially concerning early disease phases. Specific treatments aimed at improving joint homoeostasis, or even counteracting tissue damage by inducing regenerative processes, might be successful in early OA, where tissue loss and anatomical changes are still at very initial stages.

Comparative pain reduction of oral non-steroidal anti-inflammatory drugs and opioids for knee osteoarthritis: systematic analytic review

OBJECTIVE

Summarize the comparative effectiveness of oral non-steroidal anti-inflammatory drugs (NSAIDs) and opioids in reducing knee osteoarthritis (OA) pain.

METHODS

Two reviewers independently screened reports of randomized controlled trials (RCTs), published in English between 1982 and 2015, evaluating oral NSAIDs or opioids for knee OA. Included studies were at least 8 weeks duration, conducted in Western Europe, the Americas, New Zealand, or Australia, and reported baseline and follow-up pain using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain subscale (0-100, 100-worst). Effectiveness was evaluated as reduction in pain, accounting for study dropout and heterogeneity.

RESULTS

Twenty-seven treatment arms (nine celecoxib, four non-selective NSAIDs [diclofenac, naproxen, piroxicam], eleven less potent opioids [tramadol], and three potent opioids [hydromorphone, oxycodone]) from 17 studies were included. NSAID and opioid studies reported similar baseline demographics and efficacy withdrawal rates; NSAID studies reported lower baseline pain and toxicity withdrawal rates. Accounting for efficacy-related withdrawals, all drug classes were associated with similar pain reductions (NSAIDs: -18; less potent opioids: -18; potent opioids: -19). Meta-regression did not reveal differential effectiveness by drug class but found that study cohorts with a higher proportion of male subjects and worse mean baseline pain had greater pain reduction. Similarly, results of the network meta-analysis did not find a significant difference in WOMAC Pain reduction for the three analgesic classes.

CONCLUSION

NSAIDs and opioids offer similar pain relief in OA patients. These data could help clinicians and patients discuss likely benefits of alternative analgesics.

Efficacy and tolerability of an undenatured type II collagen supplement in modulating knee osteoarthritis symptoms: a multicenter randomized, double-blind, placebo-controlled study

Background

Undenatured type II collagen (UC-II) is a nutritional supplement derived from chicken sternum cartilage. The purpose of this study was to evaluate the efficacy and tolerability of UC-II for knee osteoarthritis (OA) pain and associated symptoms compared to placebo and to glucosamine hydrochloride plus chondroitin sulfate (GC).

Methods

One hundred ninety one volunteers were randomized into three groups receiving a daily dose of UC-II (40 mg), GC (1500 mg G & 1200 mg C), or placebo for a 180-day period. The primary endpoint was the change in total Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) from baseline through day 180 for the UC-II group versus placebo and GC. Secondary endpoints included the Lequesne Functional Index (LFI), the Visual Analog Scale (VAS) for pain and the WOMAC subscales. Modified intent-to-treat analysis were performed for all endpoints using analysis of covariance and mixed model repeated measures, while incremental area under the curve was calculated by the intent-to-treat method.

Results

At day 180, the UC-II group demonstrated a significant reduction in overall WOMAC score compared to placebo (p = 0.002) and GC (p = 0.04). Supplementation with UC-II also resulted in significant changes for all three WOMAC subscales: pain (p = 0.0003 vs. placebo; p = 0.016 vs. GC); stiffness (p = 0.004 vs. placebo; p = 0.044 vs. GC); physical function (p = 0.007 vs. placebo). Safety outcomes did not differ among the groups.

Conclusion

UC-II improved knee joint symptoms in knee OA subjects and was well-tolerated. Additional studies that elucidate the mechanism for this supplement’s actions are warranted.

Trial registration

CTRI/2013/05/003663; CTRI/2013/02/003348.

Early joint degeneration and antagonism between growth factors and reactive oxygen species. Is non-surgical management possible?

PURPOSE

in pathological conditions such as osteo-arthritis (OA), overproduction of reactive oxygen species (ROS) may overwhelm the antioxidant defenses of chondrocytes, thus promoting oxidative stress and cell death. It can be hypothesized that increasing the antioxidant machinery of chondrocytes may prevent the age-associated progression of this disease. Growth factors (GFs) play an important role in promoting both the resolution of inflammatory processes and tissue repair. In view of these considerations, we set out to investigate the protective effect, against H2O2-induced oxidative cell death, potentially exerted by fluid drained from the joint postoperatively.

METHODS

the present study was conducted in 20 patients diagnosed with bilateral knee osteoarthritis and treated, between January 2013 and June 2014, with prosthetic knee implantation on the side more affected by the arthritic process, together with intraoperative placement of a closed-circuit drainage aspiration system. As a result, 20 different serum samples were collected from the drained articular fluid, prepared using two different methodologies. In addition, forty blood serum samples were obtained and prepared: 20 from the surgically treated patients and 20 from healthy controls. The present work was undertaken to investigate the potential protective effect of sera obtained from articular fluid drainage against hydrogen peroxide-induced oxidative stress in cultured human chondrocytes.

RESULTS

exposure of chondrocytes to hydrogen peroxide elicited a dose-dependent increase in oxidative stress and chondrocyte cell death, phenomena that were significantly counteracted by the pre-treatment of cell cultures with sera from articular fluid drainage.

CONCLUSIONS

oxidatively stressed chondrocytes treated with sera obtained from articular fluid drainage lived longer than those treated with blood serum samples and longer than untreated ones.

CLINICAL RELEVANCE

synovial fluids are usually discarded once the drainage reservoir is full; instead they could benefit the patients from whom they are collected, as they are rich in growth factors and they may act as antagonists of ROS effects. Accordingly, they could be used to treat chondropathies, early OA, and mild OA located in other sites.

Osteoarthritis year in review 2015: clinical

The purpose of this review is to highlight clinical research in osteoarthritis (OA). A literature search was conducted using PubMed (http://www.ncbi.nlm.nih.gov/pubmed/) with the search terms "osteoarthritis [All Fields] AND treatment [All Fields]" and the following limits activated: humans, English language, all adult 19+ years, published between April 1, 2014 and April 1, 2015. A second literature search was then conducted with the search terms "osteoarthritis [All Fields] AND epidemiology [All Fields]", with the same limits. Reports of surgical outcome, case series, surgical technique, tissue sample or culture studies, trial protocols, and pilot studies were excluded. Of 1523, 150 were considered relevant. Among epidemiologic and observational clinical studies, themes included physical activity, early knee OA, and confidence/instability/falls. Symptom outcomes of pharmacologic treatments were reported for methotrexate, adalimumab, anti-nerve growth factor monoclonal antibodies, strontium ranelate, bisphosphonates, glucosamine, and chondroitin sulfate, and structural outcomes of pharmacologic treatments for strontium ranelate, recombinant human fibroblast growth factor 18, and glucosamine and chondroitin sulfate. Symptom outcomes of non-pharmacologic interventions were reported for: neuromuscular exercise, quadriceps strengthening, weight reduction and maintenance, TENS, therapeutic ultrasound, stepped care strategies, cognitive behavior therapy for sleep disturbance, acupuncture, gait modification, booster physical therapy, a web-based therapeutic exercise resource center for knee OA; hip physical therapy for hip OA; and joint protection and hand exercises for hand OA. Structure outcomes of non-pharmacologic interventions were reported for patellofemoral bracing.

Glucosamine Hydrochloride but Not Chondroitin Sulfate Prevents Cartilage Degradation and Inflammation Induced by Interleukin-1α in Bovine Cartilage Explants

OBJECTIVE

Glucosamine hydrochloride (GH) and chondroitin sulfate (CS) are commonly used for the treatment of osteoarthritis (OA). The aim of this study was to assess their effects, alone and in combination, on preventing aggrecan degradation and inflammation in an in vitro model of OA.

DESIGN

To test the effects of GH and/or CS as a preventative treatment, cartilage explants were pretreated with the compound(s) using concentrations that showed no detrimental effect on chondrocyte viability. Interleukin-1α (IL-1α) was added to induce cartilage degradation, supernatant and explants were analyzed for proteoglycan degradation products, aggrecanase mRNA expression and activity, and for the release of inflammatory markers.

RESULTS

Following treatment with IL-1α, 2 mg/mL dose of GH pretreatment was associated with a reduction of glycosaminoglycan release, reduced generation of the pathological interglobular domain aggrecan catabolites, decreased mRNA levels of ADAMTS-4 and -5 and reduced activity of ADAMTS-4. In contrast, CS alone did not have a significant effect on IL-1α-induced cartilage degradation and the addition of 0.4 mg/mL CS to 2 mg/mL GH did not further inhibit IL-1α-induced activity. Pretreatment with 2 mg/mL GH also reduced the release of inflammatory markers, prostaglandin E2 and nitric oxide induced by IL-1α while CS did not have a significant effect.

CONCLUSIONS

The results suggest that GH prevents cartilage degradation mediated by aggrecanases ADAMTS-4 and -5, and may also reduce inflammation. This could be part of the mechanisms by which GH is effective in maintaining joint integrity and function, and preventing or delaying early symptoms of OA.