Efficacy and safety of oral NSAIDs and analgesics in the management of osteoarthritis: Evidence from real-life setting trials and surveys

The role of obesity and adipose tissue dysfunction in osteoarthritis pain

Obesity has a pivotal and multifaceted role in pain associated with osteoarthritis (OA), extending beyond the mechanistic influence of BMI. It exerts its effects both directly and indirectly through various modifiable risk factors associated with OA-related pain. Adipose tissue dysfunction is highly involved in OA-related pain through local and systemic inflammation, immune dysfunction, and the production of pro-inflammatory cytokines and adipokines. Adipose tissue dysfunction is intricately connected with metabolic syndrome, which independently exerts specific effects on OA-related pain, distinct from its association with BMI. The interplay among obesity, adipose tissue dysfunction and metabolic syndrome influences OA-related pain through diverse pain mechanisms, including nociceptive pain, peripheral sensitization and central sensitization. These complex interactions contribute to the heightened pain experience observed in individuals with OA and obesity. In addition, pain management strategies are less efficient in individuals with obesity. Importantly, therapeutic interventions targeting obesity and metabolic syndrome hold promise in managing OA-related pain. A deeper understanding of the intricate relationship between obesity, metabolic syndrome and OA-related pain is crucial and could have important implications for improving pain management and developing innovative therapeutic options in OA.

Recent advancements in microspheres mediated targeted delivery for therapeutic interventions in osteoarthritis

Osteoarthritis (OA), affecting around 240 million people globally is a major threat. Currently, available drugs only treat the symptoms of OA; they cannot reverse the disease's progression. The delivery of drugs to afflicted joints is challenging because of poor vasculature of articular cartilage results in their less bioavailability and quick elimination from the joints. Recently approved drugs such as KGN and IL-1 receptor antagonists also encounter challenges because of inadequate formulations. Therefore, microspheres could be a potential player for the intervention of OA owing to its excellent physicochemical properties. This review primarily focuses on microspheres of distinct biomaterials acting as cargo for drugs and biologicals via different delivery routes in the effective management of OA. Microspheres can improve the efficacy of therapeutics by targeting strategies at specific body locations. This review also highlights clinical trials conducted in the last few decades.

Functional Nanomaterials for the Treatment of Osteoarthritis

Osteoarthritis (OA) is the most common degenerative joint disease, affecting more than 595 million people worldwide. Nanomaterials possess superior physicochemical properties and can influence pathological processes due to their unique structural features, such as size, surface interface, and photoelectromagnetic thermal effects. Unlike traditional OA treatments, which suffer from short half-life, low stability, poor bioavailability, and high systemic toxicity, nanotherapeutic strategies for OA offer longer half-life, enhanced targeting, improved bioavailability, and reduced systemic toxicity. These advantages effectively address the limitations of traditional therapies. This review aims to inspire researchers to develop more multifunctional nanomaterials and promote their practical application in OA treatment.

TMF suppresses chondrocyte hypertrophy in osteoarthritic cartilage by mediating the FOXO3a/BMPER pathway

Osteoarthritis (OA) is a disease of the joints, characterized by chronic inflammation, cartilage destruction and extracellular matrix (ECM) remodeling. Aberrant chondrocyte hypertrophy promotes cartilage destruction and OA development. Collagen X, the biomarker of chondrocyte hypertrophy, is upregulated by runt-related transcription factor 2 (Runx2), which is mediated by the bone morphogenetic protein 4 (BMP4)/Smad1 signaling pathway. BMP binding endothelial regulator (BMPER), a secreted glycoprotein, acts as an agonist of BMP4. 5,7,3',4'-tetramethoxyflavone (TMF) is a natural flavonoid derived from Murraya exotica L. Results of our previous study demonstrated that TMF exhibits chondroprotective effects against OA development through the activation of Forkhead box protein O3a (FOXO3a) expression. However, whether TMF suppresses chondrocyte hypertrophy through activation of FOXO3a expression and inhibition of BMPER/BMP4/Smad1 signaling remains unknown. Results of the present study revealed that TMF inhibited collagen X and Runx2 expression, inhibited BMPER/BMP4/Smad1 signaling, and activated FOXO3a expression; thus, protecting against chondrocyte hypertrophy and OA development. However, BMPER overexpression and FOXO3a knockdown impacted the protective effects of TMF. Thus, TMF inhibited chondrocyte hypertrophy in OA cartilage through mediating the FOXO3a/BMPER signaling pathway.

Safety of Oral and Topical Nonsteroidal Anti-Inflammatory Drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used to manage mild to moderate pain. While limited use is appropriate for many patients, there are safety concerns with use in certain patient populations or with long-term use of these agents. Topical NSAIDs may provide analgesic benefits while decreasing the overall risks of adverse effects. This article will review safety information for both oral and topical NSAIDs.

Screening of poly-beta amino ester coated emulsion of ketorolac for cartilage delivery

Osteoarthritis (OA) is a prevalent chronic health condition necessitating effective treatment strategies. Globally, there were 86 million people with incident knee osteoarthritis in 2020. Pain management remains the primary approach to OA as the nature of cartilage poses challenges for drug delivery. An emulsion-based delivery system, using a class of positively charged and hydrolysable polymers (poly-beta-amino-esters) to coat oil droplets containing drugs, has been shown to enhance and prolong drug localization in ex vivo cartilage models. As the properties of the polymers used in this technology strongly depend on the monomers used in the synthesis, this study presents the screening of a wide range of PBAEs as droplet coating agents and using ketorolac as a model of nonsteroidal anti-inflammatory drugs. The emulsions prepared with this PBAE library were characterized, and drug localisation and retention were evaluated in both native and glycosaminoglycan (GAG) depleted cartilage ex vivo models. Optimal candidates were identified and tested in an ex vivo model showing the ability to protect chondrocyte cell viability and increase both GAG and collagen contents in cartilage exposed to cytokine (IL-1α) simulating acute cartilage damage. This work demonstrates the potential of PBAE coated emulsion as a delivery system for effective drug delivery in OA treatment.

Time-Dependent Effect of Eggshell Membrane on Monosodium-Iodoacetate-Induced Osteoarthritis: Early-Stage Inflammation Control and Late-Stage Cartilage Protection

Osteoarthritis (OA) is a chronic degenerative joint disease that causes chronic pain, swelling, stiffness, disability, and significantly reduces the quality of life. Typically, OA is treated using painkillers and non-steroidal anti-inflammatory drugs (NSAIDs). While current pharmacologic treatments are common, their potential side effects have prompted exploration into functional dietary supplements. Recently, eggshell membrane (ESM) has emerged as a potential functional ingredient for joint and connective tissue disorders due to its clinical efficacy in relieving joint pain and stiffness. Despite promising clinical evidence, the effects of ESM on OA progression and its mechanism of action remain poorly understood. This study evaluated the efficacy of Ovomet®, a powdered natural ESM, against joint pain and disease progression in a monosodium iodoacetate (MIA)-induced rodent model of OA in mice and rats. The results demonstrate that ESM significantly alleviates joint pain and attenuates articular cartilage destruction in both mice and rats that received oral supplementation for 5 days prior to OA induction and for 28 days thereafter. Interestingly, ESM significantly inhibited mRNA expression levels of pro-inflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), as well as inflammatory mediators, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase in the knee joint cartilage at the early stage of OA, within 7 days after OA induction. However, this effect was not observed in the late stage at 28 days after OA induction. ESM further attenuates the induction of protein expression for cartilage-degrading enzymes like matrix metalloproteinase (MMPs) 3 and 13, and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5), in the late-stage. In addition, MIA-induced reduction of the protein expression levels of cartilage components, cartilage oligomeric matrix protein (COMP), aggrecan (ACAN) and collagen type II α-1 chain (COL2α1), and cartilage extracellular matrix (ECM) synthesis promoting transcriptional factor SRY-Box 9 (SOX-9) were increased via ESM treatment in the cartilage tissue. Our findings suggest that Ovomet®, a natural ESM powder, is a promising dietary functional ingredient that can alleviate pain, inflammatory response, and cartilage degradation associated with the progression of OA.

Discovery of new 2-(3-(naphthalen-2-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazole derivatives with potential analgesic and anti-inflammatory activities: In vitro, in vivo and in silico investigations

Joining the global demand for the discovery of potent NSAIDs with minimized ulcerogenic effect, new pyrazole clubbed thiazole derivatives 5a-o were designed and synthesized. The new derivatives were initially evaluated for their analgesic activity. Eight compounds 5a, 5c, 5d, 5e, 5f, 5h, 5m, and 5o showed higher activity than Indomethacin (potency = 105-130 % vs. 100 %). Subsequently, they were picked for further evaluation of their anti-inflammatory activity, ulcerogenic liability as well as toxicological studies. Derivatives 5h and 5m showed a potential % edema inhibition after 3 h (79.39 % and 72.12 %, respectively), with a promising safety profile and low ulcer indices (3.80 and 3.20, respectively). The two compounds 5h and 5m were subjected to in vitro COX-1 and COX-2 inhibition assay. The candidate 5h showed nearly equipotent COX-1 inhibition (IC50 = 38.76 nM) compared to the non-selective reference drug Indomethacin (IC50 = 35.72 nM). Compound 5m expressed significant inhibitory activities and a higher COX-2 selectivity index (IC50 = 87.74 nM, SI = 2.05) in comparison with Indomethacin (SI = 0.52), with less selectivity than Celecoxib (SI = 8.31). Simulation docking studies were carried out to gain insights into the binding interaction of compounds 5h and 5m in the vicinity of COX-1 and COX-2 enzymes that illustrated the importance of pyrazole clubbed thiazole core in hydrogen bonding interactions. The thiazole motif of compounds 5h and 5m exhibited a well orientation toward COX-1 Arg120 key residue by hydrogen bonding interactions. Compound 5h revealed an additional arene-cation interaction with Arg120 that could rationalize its superior COX-1 inhibitory activity. Compounds 5h and 5m overlaid the co-crystallized ligand Celecoxib I differently in the active site of COX-2. Compound 5m showed an enhanced accommodation with binding energy of - 6.13 vs. - 1.70 kcal/mol of compounds 5h. The naphthalene ring of compound 5m adopted the Celecoxib I benzene sulfonamide region that is stabilized by hydrogen-arene interactions with the hydrophobic sidechains of the key residues Ser339 and Phe504. Further, the core structure of compound 5m, pyrazole clubbed thiazole, revealed deeper hydrophobic interactions with Ala513, Leu517 and Val509 residues. Finally, a sensitive and accurate UPLC-MS/MS method was developed for the simultaneous estimation of some selected promising pyrazole derivatives in rat plasma. Accordingly, compounds 5h and 5m were suggested to be promising potent analgesic and anti-inflammatory agents with improved safety profiles and a novel COX isozyme modulation activity.

Transient receptor potential vanilloid 1: A potential therapeutic target for the treatment of osteoarthritis and rheumatoid arthritis

This study aims to determine the molecular mechanisms and analgesic effects of transient receptor potential vanilloid 1 (TRPV1) in the treatments of osteoarthritis (OA) and rheumatoid arthritis (RA). We summarize and analyse current studies regarding the biological functions and mechanisms of TRPV1 in arthritis. We search and analyse the related literature in Google Scholar, Web of Science and PubMed databases from inception to September 2023 through the multi-combination of keywords like 'TRPV1', 'ion channel', 'osteoarthritis', 'rheumatoid arthritis' and 'pain'. TRPV1 plays a crucial role in regulating downstream gene expression and maintaining cellular function and homeostasis, especially in chondrocytes, synovial fibroblasts, macrophages and osteoclasts. In addition, TRPV1 is located in sensory nerve endings and plays an important role in nerve sensitization, defunctionalization or central sensitization. TRPV1 is a non-selective cation channel protein. Extensive evidence in recent years has established the significant involvement of TRPV1 in the development of arthritis pain and inflammation, positioning it as a promising therapeutic target for arthritis. TRPV1 likely represents a feasible therapeutic target for the treatment of OA and RA.

Comparing Metabolic Preconditioning and Diabetes As Risk Factors in Knee Arthroplasty Complications

BACKGROUND AND OBJECTIVES

Advanced osteoarthritis of the knee joint severely affects the patient's mobility, compounded by pre-existing comorbidities such as metabolic preconditioning (such as obesity, dyslipidemia, hyperuricemia, and insulin resistance syndrome) and both type I and type II diabetes. The success of total knee arthroplasty is influenced by knowledge and management of risk factors. The present study aims to evaluate differences in the evolution of risk factors such as obesity, injuries, and sedentary lifestyle, distinguishing those with metabolic preconditions and diabetes. The objectives of our study include (1) investigating the prevalence of obesity among patients, highlighting their proportion in the five categories of body weight; (2) analyzing statistically significant differences between research groups in terms of weight status and physical activity; (3) evaluating postoperative evolution based on the administration of nonsteroidal anti-inflammatory drugs (NSAIDs) and without NSAIDs (N-NSAIDs), with an emphasis on overweight patients and those with diabetes; and (4) examining changes in metabolic preconditioning and the incidence of postoperative injury depending on the administration of anti-inflammatory drugs.

MATERIALS AND METHODS

 A cohort involving 730 patients diagnosed with gonarthrosis was divided into two groups according to the administration of anti-inflammatory drugs in the first seven postoperative days: N-NSAIDs group (394 patients, 55.3%) and respectively NSAIDs group (319 patients, 44.7%). The prospective, observational study was conducted in terms of risk factors and complications that occurred upon treatment administration in relation to each type of intervention and implant used. The outcomes were assessed in terms of the influence on quality of life, the data being collected and interpreted for the entire cohort, and for each study year individually.

RESULTS

The results indicate that almost 69% of them were overweight, while only 31% had a normal weight. Significant differences in weight status were observed between research groups, highlighting the association between obesity and metabolic preconditions or diabetes. Physical activity was absent in a significant proportion, having a notable impact on postoperative evolution, especially in the group without metabolic precondition. Administration of anti-inflammatory drugs influenced postoperative outcomes, with significant differences in overweight and diabetic patients.

CONCLUSIONS

The findings suggest the need to manage body weight, promote physical activity, and personalize postoperative treatments, given the complex interactions between obesity, metabolic preconditions, and the administration of NSAIDs.

General Control Non-derepressible 2 Alleviates Cartilage Degeneration and Inhibits NLRP3 Inflammasome Activation in Osteoarthritis

This study aimed to evaluate the effects of general control non-derepressible 2 (GCN2) on osteoarthritis (OA) in vivo and in vitro. First, anterior cruciate ligament transection (ACLT)-induced rat model and interleukin (IL)-1β-induced ATDC5 chondrocyte were established. Hematoxylin and eosin staining and safranin O/fast green staining were employed for analyzing the histological changes in the rat cartilage. In addition, immunohistochemistry, quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, western blot, and immunofluorescence staining were employed for examining cartilage degeneration-, inflammation-, autophagy-, and NLR family pyrin domain containing 3 (NLRP3) inflammasome-associated genes expression. Moreover, 2,7-dichlorodihydrofluorescein acetoacetic acid probe was utilized for examining the intracellular reactive oxygen species. In addition, 5-ethynyl-2'-deoxyuridine assay and flow cytometry were applied for detecting chondrocyte proliferation and apoptosis IL-1β-treated ATDC5 chondrocytes. GCN2 overexpression ameliorated articular cartilage degeneration and inflammation but promoted chondrocyte autophagy in ACLT-induced OA rats. Similarly, we demonstrated that the upregulation of GCN2 could promote chondrocyte proliferation, suppress chondrocyte apoptosis, attenuate chondrocyte inflammation and extracellular matrix degradation, and promote chondrocyte autophagy. Moreover, GCN2 overexpression could inhibit the activation of NLRP3 inflammasome in IL-1β-induced ATDC5 chondrocyte. Furthermore, 3-methyladenine neutralized the protective and autophagy-promoting effects of GCN2 overexpression on ATDC5 chondrocytes. GCN2 could attenuate inflammation and cartilage degeneration, promote chondrocyte autophagy, and inhibit NLRP3 inflammasome activation in OA.

How to treat chronic pain in rheumatic and musculoskeletal diseases (RMDs) - A pharmacological review

INTRODUCTION

Chronic pain is a common symptom of rheumatic diseases that impacts patients' quality of life. While non-pharmacological approaches are often recommended as first-line treatments, pharmacological interventions are important for pain management. However, the effectiveness and safety of different pharmacological treatments for chronic pain in rheumatic diseases are unclear.

METHODS

This review critically synthesizes the current evidence base to guide clinicians in selecting appropriate pharmacological treatments for their patients, considering the expected benefits and potential risks and side effects.

RESULTS

For osteoarthritis, nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, opioids, and antidepressants are commonly used, with NSAIDs being the most recommended. In addition, topical agents, such as topical NSAIDs, are recommended for localized pain relief. For fibromyalgia, amitriptyline, serotonin and noradrenaline reuptake inhibitors (SNRIs), and gabapentinoids are commonly used, with SNRIs being the most recommended. For back pain, nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, opioids are used only for acute of flare-up pain, whereas neuropathic pain drugs are only used for chronic radicular pain. For inflammatory rheumatic diseases, disease-modifying antirheumatic drugs (DMARDs) and biological agents are recommended to slow disease progression and manage symptoms.

CONCLUSION

While DMARDs and biological agents are recommended for inflammatory rheumatic diseases, pharmacological treatments for other rheumatic diseases only alleviate symptoms and do not provide a cure for the underlying condition. The use of pharmacological treatments should be based on the expected benefits and evaluation of side effects, with non-pharmacological modalities also being considered, especially for fibromyalgia.

Phillygenin inhibits inflammation in chondrocytes via the Nrf2/NF-κB axis and ameliorates osteoarthritis in mice

Objective

Osteoarthritis (OA), widely seen in the elderly, is featured by cartilage degradation, subchondral bone remolding, and synovium inflammation. Currently, there is no cure for OA development. Phillygenin (PHI), an active ingredient from the Forsythiae Fructus, possesses many biological properties, such as anti-inflammation and anti-oxidative stress in several diseases. However, the potential effects and underlying mechanisms of PHI on OA remain unclear.

Methods

Western blotting, RT-PCR, ELISA and tissue staining were employed to explore the mechanisms by which PHI exerted a protective effect on IL-1β-induced production of pro-inflammation cytokines and extracellular matrix (ECM) degradation in primary murine chondrocytes and destabilization of the medial meniscus (DMM) mouse models.

Results

In this study, we found that PHI inhibited the production of pro-inflammation cytokines and ECM degradation induced by IL-1β in primary murine chondrocytes. Mechanically, PHI inhibited the NF-κB pathway via activating nuclear factor (erythrluteolind-derived 2)-like 2 (Nrf2). In vivo experiments also confirmed the chondroprotection of PHI in DMM mouse models.

Conclusion

PHI alleviated IL-1β-induced inflammation cytokines and ECM degradation via activating Nrf2 and inhibiting NF-κB pathway.

The translational potential of this article

This study provides a biological rationale for the use of PHI as a potential candidate for OA treatment.

Tetrandrine Represses Inflammation and Attenuates Osteoarthritis by Selective Inhibition of COX-2

OBJECTIVE

There is a lack of effective and long-term safe drugs for the treatment of osteoarthritis (OA). Tetrandrine (Tet) has been approved and used to treat rheumatoid arthritis for several decades, but its effect on OA has not been investigated. Herein, we explored the effect of Tet on OA and its underlying mechanism.

METHODS

OA was induced using destabilization of the medial meniscus (DMM) in C57BL/6J mice. The animals were randomly divided into sham, DMM, Tet, celecoxib (CXB), and indomethacin (INDO) groups. Each group was given solvent or corresponding drugs by gavage for 7 weeks after convalescence. Pathological staining, OARSI scores, micro-computed tomography and behavior tests were performed to evaluate the effects of Tet.

RESULTS

Tet remarkably alleviated cartilage injury in the knee joint, limited bone remodeling in the subchondral bone, and delayed progression of OA. Tet also significantly relieved joint pain and maintained function. Further mechanistic studies revealed that Tet lowered inflammatory cytokine levels and selectively suppressed gene and protein expression of cyclooxygenase (COX)-2 but not COX-1 (P<0.01). Tet also reduced the production of prostaglandin E2 without damaging the gastric mucosa.

CONCLUSION

We found that Tet could selectively inhibit COX-2 gene expression and decrease cytokine levels in mice, thus reducing inflammation and improving OA without obvious gastric adverse events. These results provide a scientific basis for the clinical application of Tet in the treatment of OA.

Potential of Icariin–Glucosamine Combination in the Treatment of Osteoarthritis by Topical Application: Development of Topical Formulation and In Vitro Permeation Study

The aim of this study was to develop a topically applied formulation with the potential to alleviate arthritis ailments. A combination of two active ingredients, icariin from Epimedium L. (Species: Epimedium Koreanum) extract as a potential promoter of chondrogenesis and glucosamine sulfate as a precursor of cartilage tissues, was tested. In permeation studies, the potential for skin permeation of both substances was confirmed; however, the in vitro release test did not accurately reflect the degree of skin permeation. The in vitro release of icariin was at a level of 15.0–19.0% for the plant-extract-derived icariin and 29.0–35.0% for the pure substance. The level of glucosamine sulfate release was 38.4% (on average). For icariin of both origins, the release results were higher than those obtained via oral administration (about 12.0%), which shows the potential superiority of topical application. In addition, the physicochemical parameters that affect the in vitro release and performance of topical formulations were addressed. This preliminary research and permeation analysis of the formulation produced a promising picture of its prospects regarding arthritis treatment, although further investigation is needed.

Analgesic effect of curcumin topical formulation in knee osteoarthritis patients: a clinical trial

OBJECTIVES

The aim of this study was to recognize the efficacy and safety of curcumin ointment on patients with knee osteoarthritis (OA) compare to diclofenac as standard medication.

METHODS

The topical effects of curcumin (10%) and diclofenac (1%) ointments were assessed through the visual analog scale (VAS) and Western Ontario and McMaster Universities Arthritis (WOMAC) index after three times a day administration for two weeks in 60 patients.

RESULTS

Desirable effects compared to the pre-treatment period were observed after two weeks of continuous treatment. Based on our results, VAS and WOMAC index were altered after treatment significantly (p<0.0001).

CONCLUSIONS

Two-week use of curcumin ointment could ameliorate the pain, stiffness and function disability in patients with OA.

Sustained inhibition of CC-chemokine receptor-2 via intraarticular deposition of polymeric microplates in post-traumatic osteoarthritis

Posttraumatic osteoarthritis (PTOA) is mostly treated via corticosteroid administration, and total joint arthroplasty continues to be the sole effective intervention in severe conditions. To assess the therapeutic potential of CCR2 targeting in PTOA, we used biodegradable microplates (µPLs) to achieve a slow and sustained intraarticular release of the CCR2 inhibitor RS504393 into injured knees and followed joint damage during disease progression. RS504393-loaded µPLs (RS-µPLs) were fabricated via a template-replica molding technique. A mixture of poly(lactic-co-glycolic acid) (PLGA) and RS504393 was deposited into 20 × 10 μm (length × height) wells in a polyvinyl alcohol (PVA) square-patterned template. After physicochemical and toxicological characterizations, the RS504393 release profile from µPL was assessed in PBS buffer. C57BL/6 J male mice were subjected to destabilization of the medial meniscus (DMM)/sham surgery, and RS-µPLs (1 mg/kg) were administered intraarticularly 1 week postsurgery. Administrations were repeated at 4 and 7 weeks post-DMM. Drug free-µPLs (DF-µPLs) and saline injections were performed as controls. Mice were euthanized at 4 and 10 weeks post-DMM, corresponding to the early and severe PTOA stages, respectively. Knees were evaluated for cartilage structure score (ACS, H&E), matrix loss (safranin O score), osteophyte formation and maturation from cartilage to bone (cartilage quantification), and subchondral plate thickness. The RS-µPL architecture ensured the sustained release of CCR2 inhibitors over several weeks, with ~ 20% of RS504393 still available at 21 days. This prolonged release improved cartilage structure and reduced bone damage and synovial hyperplasia at both PTOA stages. Extracellular matrix loss was also attenuated, although with less efficacy. The results indicate that local sustained delivery is needed to optimize CCR2-targeted therapies.

Applications and prospects of intra-articular drug delivery system in arthritis therapeutics

Arthritis is a kind of chronic disease that affects joints and muscles with the symptoms of joint pain, inflammation and limited movement of joints. Among various clinical therapies, drug therapy has been extensively applied because of its accessibility, safety and effectiveness. In recent years, the intra-articular injection has dramatic therapeutic effects in treating arthritis with high patient compliance and low side effects. In this review, we will introduce pathology of arthritis, along with the accessible treatment and diagnosis methods, then we will summarize major advances of current hopeful intra-articular delivery systems such as microspheres, hydrogels, nanoparticles and liposomes. At last, some safety assessments in the preclinical work and the main challenges for the further development of intra-articular treatment were also discussed.

Relative safety and efficacy of topical and oral NSAIDs in the treatment of osteoarthritis: A systematic review and meta-analysis

BACKGROUND

Osteoarthritis (OA) often affects the hands, knees, and hip joints, causing considerable pain and disability, and often affecting the patient's quality of life. Non-steroidal anti-inflammatory drugs (NSAIDs) are common pain relievers often applied as first line therapies for OA. However, prolonged NSAIDs application can have unwanted side effects. Given this, this study was designed to systematically evaluate the efficacy and safety of topical and oral NSAIDs for the treatment of OA.

METHODS

We searched the PubMed, Embase, Cochrane Library, and Web of Science databases for relevant papers from their inception dates to May 2021. Our study only included randomized controlled trials comparing topical and oral NSAIDs and all data were analyzed using Review Manager version 5.3 (RevMan version 5.3).

RESULTS

We identified 8 RCTs (2096 patients with OA), for evaluation and revealed that, in general, topical and oral NSAIDs presented with similar efficacies for the treatment of OA. The Western Ontario and McMaster Osteoarthritis Index for assessing pain relief in OA patients was (standardized mean difference [SMD] 0.07; 95%CI -0.02, 0.17) and visual analog scale was (SMD -0.01; 95%CI -0.02, 0.18), and improved stiffness in OA patients (SMD 0.09; 95%Cl 0.03, 0.20).

CONCLUSIONS

Topical NSAIDs are as effective as oral NSAIDs for the treatment of OA and both topical and oral NSAIDs are equally effective in reducing pain and improving physical function in OA patients. In terms of safety, a larger number of samples are still needed to determine if there are any differences in the safety profile of topical or oral NSAIDs.

REGISTRATION NUMBER

INPLASY 2021110009.

Integrated Serum Metabolomics and Network Pharmacology to Reveal the Interventional Effects of Quzhi Decoction against Osteoarthritis Pain

Objectives

Chronic pain, the main symptom of knee osteoarthritis (OA), remains the primary reason for decreased functional capacity. Quzhi decoction, a TCM prescription, is effective in treating chronic pain in OA, but the potential mechanisms require further exploration.

Methods

An anterior cruciate ligament transection (ACLT) rat model was established, and pain-like behavior was evaluated. Metabolomics analysis of serum samples was performed to identify differential metabolites, and network pharmacology was used to identify potential targets of Quzhi decoction for the treatment of OA. Finally, we constructed a comprehensive network of serum metabolomics and network pharmacology. At the same time, the obtained key targets were verified by molecular docking.

Results

Quzhi decoction was shown to attenuate pain-like behavior and joint inflammation in OA rats. Through serum metabolomics, thirty potentially significant metabolites were found to be involved in the therapeutic effects of Quzhi decoction against OA pain. According to network pharmacology, 107 active drug components were matched with 115 disease targets, which was partly consistent with the metabolomics findings. Further analysis focused on 6 key targets, including CYP3A4, PLA2G4A, PTGS1, PTGS2, TYR, and ALOX5, and their associated core metabolites and pathways. Molecular docking results showed that the related targets had high affinity with the active pharmaceutical ingredients in Quzhi decoction.

Conclusion

The effect of Quzhi decoction on OA pain may be related to the inhibition of joint inflammation, mainly through disturbing arachidonic acid metabolism, tyrosine metabolism, and leukotriene metabolism. Further systematic molecular biology experiments are needed to verify the accurate mechanism.

Development of Nanomaterials to Target Articular Cartilage for Osteoarthritis Therapy

Osteoarthritis (OA) is an obstinate, degradative, and complicated disease that has drawn much attention worldwide. Characterized by its stubborn symptoms and various sequela, OA causes much financial burden on both patients and the health system. What’s more, conventional systematic therapy is not effective enough and causes multiple side effects. There’s much evidence that nanoparticles have unique properties such as high penetration, biostability, and large specific surface area. Thus, it is urgent to exploit novel medications for OA. Nanomaterials have been sufficiently studied, exploiting diverse nano-drug delivery systems (DDSs) and targeted nano therapeutical molecules. The nanomaterials are primarily intra-articular injected under the advantages of high topical concentration and low dosage. After administration, the DDS and targeted nano therapeutical molecules can specifically react with the components, including cartilage and synovium of a joint in OA, furthermore attenuate the chondrocyte apoptosis, matrix degradation, and macrophage recruitment. Thus, arthritis would be alleviated. The DDSs could load with conventional anti-inflammatory drugs, antibodies, RNA, and so on, targeting chondrocytes, synovium, or extracellular matrix (ECM) and releasing the molecules sequentially. The targeted nano therapeutical molecules could directly get to the targeted tissue, alleviating the inflammation and promoting tissue healing. This review will comprehensively collect and evaluate the targeted nanomaterials to articular cartilage in OA.

Identification of SCRG1 as a Potential Therapeutic Target for Human Synovial Inflammation

Synovial inflammation of joint tissue is the most important cause of tissue damage, joint destruction, and disability and is associated with higher morbidity or mortality. Therefore, this study aims to identify key genes in osteoarthritis synovitis tissue to increase our understanding of the underlying mechanisms of osteoarthritis and identify new therapeutic targets. Five GEO datasets with a total of 41 normal synovial membrane tissues and 45 osteoarthritis synovial membrane samples were used for analysis, and seven common differential genes were identified. The classification model constructed by LASSO analysis showed that six genes including CDKN1A, FOSB, STMN2, SLC2A3, TAC, and SCRG1 can be used as biomarkers of osteoarthritis, and the SCRG1 gene shows importance in osteoarthritis. Furthermore, drug database enrichment found that these six DEGs may be the drug targets of synovitis in osteoarthritis, and Valproic Acid CTD 00006977 may be a potential targeted therapeutic drug of SCRG1. Spearman correlation analysis was performed on the SCRG1 gene, and 27 genes with consistent expression were obtained. Functional analysis showed that 27 genes were mainly involved in metabolism, complement, antigen presentation, apoptosis, and regulation of immune pathways. The co-regulatory network of TFs-miRNA suggested that the SCRG1 gene may be regulated by hsa-miR-363-3p miRNA. In conclusion, SCRG1, as a diagnostic marker of osteoarthritis, co-regulates immune-related pathways through the interaction of related proteins, playing an important role in the occurrence and development of osteoarthritis, which may be a novel drug target.

Non-steroidal anti-inflammatory drugs (NSAIDs), pain and aging: Adjusting prescription to patient features

A narrative review of papers published from January 2011 to December 2021, after a literature search in selected databases using the terms "pharmacokinetics", "ibuprofen", "diclofenac", "acemetacin", "naproxen", "etodolac" and "etoricoxib" was performed. From 828 articles identified, only eight met the inclusion criteria. Selective COX-2 inhibitors are associated with higher cardiovascular risk, while non-selective COX inhibitors are associated with higher gastrointestinal risk. NSAIDs with lower renal excretion with phase 2 metabolism are less likely to induce adverse effects and drug-drug interactions. Patients with frequent NSAID use needs, such as elderly patients and patients with cardiovascular disease or impaired renal function, will benefit from lower renal excretion (e.g. acemethacin, diclofenac, and etodolac) (level of evidence 3). Polymedicated patients, elderly patients, and patients with chronic alcohol abuse will be at a lower risk for adverse effects with NSAIDs that undergo phase 2 liver biotransformation, namely, acemethacin and diclofenac (level of evidence 3). Young patients, patients dealing with acute pain, or with active and/or chronic symptomatic gastritis, selective COX-2 inhibitors (celecoxib or etoricoxib) may be a better option (level of evidence 2). Knowing the individual characteristics of the patients, combined with knowledge on basic pharmacology, offers greater safety and better adherence to therapy. PERSPECTIVE: Although there are several NSAIDs options to treat pain, physicians usually take special care to its prescription regarding cardiovascular and gastrointestinal side effects, despite the age of the patient. In this paper, based on the best evidence, the authors present a review of the safest NSAIDs to use in the elderly.

Use of mesoporous polydopamine nanoparticles as a stable drug-release system alleviates inflammation in knee osteoarthritis

Osteoarthritis drugs are often short-acting; therefore, to enhance their efficacy, long-term, stable-release, drug-delivery systems are urgently needed. Mesoporous polydopamine (MPDA), a natural nanoparticle with excellent biocompatibility and a high loading capacity, synthesized via a self-aggregation-based method, is frequently used in tumor photothermal therapy. Here, we evaluated its efficiency as a sustained and controlled-release drug carrier and investigated its effectiveness in retarding drug clearance. To this end, we used MPDA as a controlled-release vector to design a drug-loaded microsphere system (RCGD423@MPDA) for osteoarthritis treatment, and thereafter, tested the efficacy of the system in a rat model of osteoarthritis. The results indicated that at an intermediate drug-loading dose, MPDA showed high drug retention. Furthermore, the microsphere system maintained controlled drug release for over 28 days. Our in vitro experiments also showed that drug delivery using this microsphere system inhibited apoptosis-related cartilage degeneration, whereas MPDA-only administration did not show obvious cartilage degradation improvement effect. Results from an in vivo osteoarthritis model also confirmed that drug delivery via this microsphere system inhibited cartilage damage and proteoglycan loss more effectively than the non-vectored drug treatment. These findings suggest that MPDA may be effective as a controlled-release carrier for inhibiting the overall progression of osteoarthritis. Moreover, they provide insights into the selection of drug-clearance retarding vectors, highlighting the applicability of MPDA in this regard.

Effectiveness of the Thermal Genicular Nerve Radiofrequency Ablation Therapy Under Fluoroscopy in Patients with Non-operative Advanced Stage Knee Osteoarthritis: 1-Year Follow-Up Results

BACKGROUND

In this study, our aim was to present the 1-year results of the effect of thermal genicular nerve radiofrequency ablation (GNRFA) therapy on pain and functional outcomes in patients with advanced knee osteoarthritis.

MATERIALS AND METHODS

After retrospectively examining the hospital records, 49 knees of 35 patients who had undergone thermal RFA of the superior medial, superior lateral, and inferior medial branches of the genicular nerve under fluoroscopic guidance between July 2019 and December 2020 were included in the study. The visual analog scale (VAS) scores of the patients were recorded before RFA, on the day of RFA, and at the first, sixth, and 12th months postoperatively, as well as their Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores before RFA and at the 12th month postoperatively. Complications developed after the procedure and during the follow-up period were screened.

RESULTS

Twenty-five of the patients were females and 10 males, with a mean age of 77.3 ± 7.9 years (range 61-92 years). The mean VAS score was 8.4 ± 0.9 before RFA, and as 1.7 ± 1.0 right after the procedure, 2.4 ± 1.7 at the first month, 3.4 ± 1.8 at the sixth month, and 4.4 ± 1.9 at the 12th month (p < 0.01). In terms of the WOMAC score, the average value was 69.7 ± 6.4 before the treatment and 36.1 ± 11.8 at the final follow-up at the 12th month (p < 0.01). No complications were observed in any patient during the treatment or the follow-up period.

CONCLUSION

Non-surgical thermal GNRFA therapy of knee osteoarthritis provides significant outcomes in terms of pain and functionality, with no significant systemic or local side effects. Therefore, the technique can be considered as an alternative to other methods when treating advanced osteoarthritis.

Highlighting the Benefits of Rehabilitation Treatments in Hip Osteoarthritis

Background and objectives: Due to its frequency and possible complications, hip arthrosis or hip osteoarthritis (hip OA) has a high social impact, its advanced stages eventually leading to irreversible lesions involving major complications or surgery. In the early stages, conservative treatment plays a key role in the prophylaxis of complications and in slowing down the degenerative process. The association between an appropriate drug therapy (DT) and a rehabilitation treatment (RT)—including individualized physical therapy (PT) and adapted occupational therapy (OT)—provides good results. Our objective was to highlight the benefits of associating RT with DT in patients with hip OA. Materials and Methods: An observational follow-up study was conducted between 2018−2021, which included 100 patients with hip OA divided into two groups: the study group—group A (50 subjects who complied with RT) and the control group—group B (who did not comply with RT). To evaluate them, the evolution of the Lequesne hip index (LHI), Tinetti test (TT) and the hip joint mobility: flexion (FH) and abduction (AH) were monitored before the beginning of the study (T0) and after one-year (T1) for each patient. The mean values of the parameters, the standard deviations, the frequency intervals, as well as the tests of statistical significance were calculated using the Student method (t-test) and χ2, ANOVA (Bonferroni) being used to compare the means. Results: Compared to the evolution of group B, improvements were observed in group A, as follows: in LHI group A (p = 0.023) vs. group B (p = 0.650); in TT group A (p = 0.011) vs. group B (p < 0.001); in FH group A (p = 0.001) vs. group B (p = 0.025); in AH group A (p = 0.001) vs. group B (p < 0.001). BMI changes were non-significant in both groups A (p = 0.223) and B (p = 0.513). Evaluating group A, the most significant improvements of the studied parameters were observed in the age group 41−50 years. Conclusions: The study reveals the benefits of combining RT with DT in patients with especially early-stage hip OA, aged up to 50 years old.

Anti-Dlx5 Retards the Progression of Osteoarthritis through Inhibiting Chondrocyte Hypertrophy and Apoptosis

Osteoarthritis is a common degenerative joint disease that can cause pain and disability in patients. There is still a lack of effective treatments to improve pathological changes of osteoarthritis cartilages and reverse the progression of osteoarthritis. Our study aimed to investigate the role of Dlx5 in papain-induced osteoarthritis. Osteoarthritis was induced through intraarticular injection of papain. The pathological damage of cartilage tissues was analyzed by H&E staining. The apoptosis of cartilage tissues was detected by TUNEL assay. Immunohistochemical staining was performed to detect DLX5 and BMP-2. Western blot was performed to detect the expressions of SP7, caspase-3, and MYC. The results showed that administration of anti-Dlx5 improved pathological changes of osteoarthritis cartilages, characterized by decreased chondrocyte proliferation, chondrocyte hypertrophy, and matrix damage. Anti-Dlx5 treatment decreased the expressions of BMP-2 and SP7, which are positive regulators of chondrocyte hypertrophy. Moreover, MYC and caspase-3, the critical mediators for chondrocyte apoptosis, were both decreased after anti-Dlx5 treatment. In conclusion, anti-Dlx5 retarded the progression of osteoarthritis by downregulating chondrocyte hypertrophy and chondrocyte apoptosis-related genes. Our findings suggests that Dlx5 is a promising target for osteoarthritis treatment.

The Role of Medicinal and Aromatic Plants against Obesity and Arthritis: A Review

Obesity is a significant health concern, as it causes a massive cascade of chronic inflammations and multiple morbidities. Rheumatoid arthritis and osteoarthritis are chronic inflammatory conditions and often manifest as comorbidities of obesity. Adipose tissues serve as a reservoir of energy as well as releasing several inflammatory cytokines (including IL-6, IFN-γ, and TNF-α) that stimulate low-grade chronic inflammatory conditions such as rheumatoid arthritis, osteoarthritis, diabetes, hypertension, cardiovascular disorders, fatty liver disease, oxidative stress, and chronic kidney diseases. Dietary intake, low physical activity, unhealthy lifestyle, smoking, alcohol consumption, and genetic and environmental factors can influence obesity and arthritis. Current arthritis management using modern medicines produces various adverse reactions. Medicinal plants have been a significant part of traditional medicine, and various plants and phytochemicals have shown effectiveness against arthritis and obesity; however, scientifically, this traditional plant-based treatment option needs validation through proper clinical trials and toxicity tests. In addition, essential oils obtained from aromatic plants are being widely used as for complementary therapy (e.g., aromatherapy, smelling, spicing, and consumption with food) against arthritis and obesity; scientific evidence is necessary to support their effectiveness. This review is an attempt to understand the pathophysiological connections between obesity and arthritis, and describes treatment options derived from medicinal, spice, and aromatic plants.

Combined Mesenchymal Stem Cells and Cartilage Acellular Matrix Injection Therapy for Osteoarthritis in Goats

BACKGROUND

Human umbilical cord blood-derived MSCs (hUCB-MSCs) have been studied in osteoarthritis (OA) and cartilage regeneration. Our previous study demonstrated that hUCB-MSCs combined with cartilage acellular matrix injection (CAM Inj.) represent potential therapeutic agents for structural improvement and anti-inflammatory effects in a rabbit model of OA.

METHODS

Based on a previous study, this study has evaluated the safety and efficacy of hUCB-MSCs combined with CAM Inj. in an anterior cruciate ligament transection (ACLT) with medial meniscectomy (MMx) in a goat model. In this study, 27 goats were divided into 5 groups: normal (n = 3), OA (n = 6), OA + CAM Inj. (n = 6), OA + hUCB-MSCs (n = 6), and OA + hUCB-MSCs + CAM Inj. (n = 6). Lameness and radiographic parameters were assessed 6 months after administration, and macroscopic and histological evaluations of the goat articular cartilage were performed 6 months after intervention.

RESULTS

The results showed significant improvement in lameness score only in the OA + hUCB-MSCs group at 5 months after treatment (*p < 0.05), whereas the K&L score showed significant improvement only in the OA + hUCB-MSCs + CAM Inj. group 6 months after intervention (*p < 0.05). In addition, the gross findings showed significance in OA + CAM Inj. and OA + hUCB-MSCs + CAM Inj. groups 6 months after treatment (*p < 0.05 and **p < 0.01).

CONCLUSION

In conclusion, treatment with a combination of hUCB-MSCs and CAM Inj. reduced OA symptoms and induced effective cartilage tissue repair in a goat model. We suggest the combination of hUCB-MSCs and CAM Inj. as an alternative therapy for OA.

The Emerging Role of Cyclodextrin Metal–Organic Frameworks in Ostheotherapeutics

Metal–Organic Frameworks (MOFs) are a class of coordination compounds with high versatility of design and a high loading ability. These properties have made them increasingly attractive for drug delivery, with research focusing mostly on the preparation of biocompatible MOFs. A suitable strategy is the use of cyclodextrins, cyclic oligosaccharides with excellent biosafety profiles. This review summarises the early steps taken in the application of cyclodextrin-coated and cyclodextrin-based MOFs in the treatment of bone-related diseases divided into three categories: cyclodextrin-coated MOFs, cyclodextrin-based MOFs and cross-linked derivatives of CD-MOFs. Applications in the delivery of bisphosphonates, osteoporotic regulating drugs and non-steroidal anti-inflammatory drugs, for osteoarthritis management, are highlighted. Lastly, the use of these materials in dentistry is exemplified with a recent report.

Increased expression of osteopontin in subchondral bone promotes bone turnover and remodeling, and accelerates the progression of OA in a mouse model

Osteopontin (OPN) has been proved to be closely related to the pathogenesis of osteoarthritis (OA), but the role of OPN in the pathogenesis of OA has not been fully clarified. Current studies on OPN in OA mostly focus on articular cartilage, synovial membrane and articular fluid, while ignoring its role in OA subchondral bone turnover and remodeling. In this study, we used a destabilization OA mouse model to investigate the role of OPN in OA subchondral bone changes. Our results indicate that increased expression of OPN accelerates the turnover and remodeling of OA subchondral bone, promotes the formation of h-type vessels in subchondral bone, and mediates articular cartilage degeneration induced by subchondral bone metabolism. In addition, our results confirmed that inhibition of PI3K/AKT signaling pathway inhibits OPN-mediated OA subchondral bone remodeling and cartilage degeneration. This study revealed the role and mechanism of OPN in OA subchondral bone, which is of great significance for exploring specific biological indicators for early diagnosis of OA and monitoring disease progression, as well as for developing drugs to regulate the metabolism and turnover of subchondral bone and alleviate the subchondral bone sclerosis of OA.

Insight into the pharmacological effects of andrographolide in musculoskeletal disorders

Andrographis paniculata (A. paniculata) is a traditional herbal medicine that has been widely used in Asian countries for hundreds of years. Andrographolide (AG) is a diterpene lactone extracted from A. paniculata. Owing to the in-depth study of pharmacological mechanisms, the therapeutic potential of AG, including its anti-inflammatory, anti-tumor, and immunoregulatory attributes, has attracted the attention of many researchers. Studies testing the therapeutic effects of AG have demonstrated desirable results in the treatment of a variety of clinical diseases. With high safety and various biological functions, AG might be a promising candidate for the treatment of musculoskeletal disorders. Here, we review all available literatures to summarize the pharmacological effects of AG and facilitate further researches on musculoskeletal diseases.

The future of deep phenotyping in osteoarthritis: How can high throughput omics technologies advance our understanding of the cellular and molecular taxonomy of the disease?

Osteoarthritis (OA) is the most common form of musculoskeletal disease with significant healthcare costs and unmet needs in terms of early diagnosis and treatment. Many of the drugs that have been developed to treat OA failed in phase 2 and phase 3 clinical trials or produced inconclusive and ambiguous results. High throughput omics technologies are a powerful tool to better understand the mechanisms of the development of OA and other arthritic diseases. In this paper we outline the strategic reasons for increasingly applying deep phenotyping in OA for the benefit of gaining a better understanding of disease mechanisms and developing targeted treatments. This editorial is intended to launch a special themed issue of Osteoarthritis and Cartilage Open addressing the timely topic of "Advances in omics technologies for deep phenotyping in osteoarthritis". High throughput omics technologies are increasingly being applied in mechanistic studies of OA and other arthritic diseases. Applying multi-omics approaches in OA is a high priority and will allow us to gather new information on disease pathogenesis at the cellular level, and integrate data from diverse omics technology platforms to enable deep phenotyping. We anticipate that new knowledge in this area will allow us to harness the power of Big Data Analytics and resolve the extremely complex and overlapping clinical phenotypes into molecular endotypes, revealing new information about the cellular taxonomy of OA and "druggable pathways", thus facilitating future drug development.

The effect of cartilage decellularized extracellular matrix-chitosan compound on treating knee osteoarthritis in rats

Knee osteoarthritis (KOA) refers to a common disease in orthopaedics, whereas effective treatments have been rarely developed. As indicated from existing studies, chondrocyte death, extracellular matrix degradation and subchondral bone injury are recognized as the pathological basis of KOA. The present study aimed to determine the therapeutic effect of decellularized extracellular matrix-chitosan (dECM-CS) compound on KOA. In this study, rat knee cartilage was decellularized, and a satisfactory decellularized extracellular matrix was developed. As suggested from the in vitro experiments, the rat chondrocytes co-cultured with allogeneic dECM grew effectively. According to the results of the alamar blue detection, dECM did not adversely affect the viability of rat chondrocytes, and dECM could up-regulate the genes related to the cartilage synthesis and metabolism. As reported from the animal experiments, dECM-CS compound could protect cartilage, alleviate knee joint pain in rats, significantly delay the progress of KOA in rats, and achieve high drug safety. In brief, dECM-CS compound shows a good therapeutic effect on KOA.

New pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-4(3H)-one hybrids linked to arene units: synthesis of potential MRSA, VRE, and COX-2 inhibitors

In the current study, we reported the tandem synthesis of two series of arene-linked pyrimidinone hybrids with related fused thieno[2,3-b]pyridine moiety. The target hybrids were prepared, in moderate to excellent yields, by the reaction of a ternary mixture of the appropriate of 3-aminothieno[2,3-b]pyridine-2-carboxylate, DMF-DMA, and a series of aryl amines in dioxane at 110 °C for 8 h. The antibacterial activity of the new hybrids was estimated against six susceptible ATCC strains. Hybrids 5g and 7g, linked to a sulfonamide unit, showed the best efficacy against S. aureus and E. faecalis strains with minimum inhibitory concentration (MIC) values of 1.7–1.8 μM, which exceed ciprofloxacin. Furthermore, some of new hybrids were examined as potential inhibitors of four different MRSA and VRE strains. Hybrids 5g and 7g demonstrated more potent efficacy than linezolid against MRSA strains with MIC values of 3.6/3.4 and 1.8/1.7 μM against ATCC:33591 and ATCC:43300 strains, respectively. The prior hybrids displayed a comparable efficacy with linezolid against VRE strains with MIC values of 7.3/6.9 and 3.6/3.4 μM against ATCC:51299 and ATCC:51575 strains, respectively. Additionally, some of the new hybrids were examined as potential COX-2 inhibitors using the reference celecoxib (IC50 of 0.117 µM). Hybrid 7g revealed more potent inhibitory efficacy than celecoxib with IC50 of 0.112 µM, whereas hybrid 5g showed almost inhibitory activity equivalent to celecoxib with IC50 of 0.121 µM. Molecular docking was performed to predict the possible binding interactions between hybrids 5g and 7g with the target COX-2 enzyme.

Melatonin Maintains Anabolic-Catabolic Equilibrium and Regulates Circadian Rhythm During Osteoarthritis Development in Animal Models: A Systematic Review and Meta-analysis

Background: The driving force behind osteoarthritis (OA) pathogenesis is an anabolic-catabolic (a/c) imbalance. Melatonin (MT) is a key player in maintaining a/c stability and mitigates OA pathogenesis, but mechanisms underlying its effects remain poorly understood.

Objectives: We performed a systematic review analyzing the experimental data that support the clinical applicability of MT in the treatment of OA pathogenesis, placing particular emphasis on the regulation of circadian rhythms and a/c balance.

Methods: Major electronic databases and grey literature were used to identify related original articles. Methodological quality of all selected studies was evaluated using the SYRCLE risk of bias tool. Pooled mean differences (MDs)/standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated to estimate the effect size.

Results: Eleven trials were included in this systematic review. Compared with the control group, MT significantly decreased the levels of interleukin-1β (IL-1β; SMD = −5.45; 95% CI [−6.78, −4.12]; p < 0.00001, and histological grading scale (SMD = −3.46; 95% CI, [−5.24, −1.68]; p < 0.0001). MT significantly increased the transforming growth factor-β1 (TGF-β1; SMD = 1.17; 95% CI [0.31, 2.03]; p < 0.0007). Furthermore, core circadian clock genes Per2 and Cry1 mRNA levels were regulated by MT treatment in OA progression.

Conclusion: MT may maintain a/c balance and regulate circadian rhythms during OA development. MT could be used in as adjunct with other interventions to manage pain and OA severity.

NGF Expression and Elevation in Hip Osteoarthritis Patients with Pain and Central Sensitization

Osteoarthritis (OA) is a chronic degenerative musculoskeletal disease that causes articular cartilage degeneration and chronic pain. Research into OA animal models suggests that elevated NGF levels in the synovium contribute to pain and central sensitization (CS). However, it is unclear whether synovial NGF contributes to CS in patients with OA. We investigated the association between synovial NGF expression and clinical assessments of pain and CS in hip OA (hOA) patients. We also aimed to identify which cells in the synovium of hOA patients express NGF. Sixty-six patients who received total hip replacement and a diagnosis of hOA were enrolled. We measured NGF mRNA expression in synovial samples obtained from 50 patients using qPCR and analyzed the correlation of NGF expression with the CS inventory (CSI) score and Japanese Orthopaedic Association (JOA) score, a clinical scoring system for OA. To identify the synovial cells expressing NGF, we analyzed NGF mRNA expression in CD14+ and CD14- cells, which represent macrophage-rich and fibroblast-rich fractions, respectively, extracted from 8 patients. To further identify which macrophage subtypes express NGF, we examined NGF mRNA expression in CD14^high and CD14^low cells sorted from 8 patients. Synovial NGF mRNA expression was negatively correlated with JOA score but positively correlated with CSI score (JOA pain, r = −0.337, P = 0.017; CSI score, r = 0.358, P = 0.011). Significantly greater levels of NGF were observed in CD14- cells compared to CD14+ cells (P = 0.036) and in CD14^high cells compared to CD14^low cells (P = 0.008). In conclusion, synovial NGF expression is correlated with the degree of pain and CS in hOA patients. NGF is predominantly expressed in synovial fibroblasts. Further, CD14^high synovial macrophages expressed higher levels of NGF. Our results may provide a novel NGF-targeted therapeutic strategy for hOA pain.

2021 revised algorithm for the management of knee osteoarthritis-the Chinese viewpoint

AIM

The European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) algorithm for the management of knee osteoarthritis (OA) is available worldwide from 2014, but in 2019 an update was published. Based on this algorithm, a Working Group (WG), including ESCEO members and Chinese experts, wished to see how the new ESCEO algorithm was perceived by Chinese experts in knee OA and how it was integrated into their clinical practice.

METHODS

A WG was held between members of the international ESCEO task force and a group of Chinese experts.

RESULTS

Non-pharmacological approach should be combined with pharmacological interventions. In step 1, symptomatic slow-acting drugs for osteoarthritis (SYSADOA) are the most important background drugs. Evidence, supported by high-quality research, is available only for crystalline glucosamine sulfate (pCGS) and chondroitin sulfate. Topical NSAIDs could be used as an additional option. In step 2, oral NSAIDs could be useful, but cardiovascular/renal/gastrointestinal profiles of the patients should be considered. Intra-articular hyaluronic acid and corticosteroids are alternative to oral NSAIDs, but the evidence is still limited. If steps 1 and 2 are not sufficient, weak opioids could be used. Overall, the conclusions of the ESCEO algorithm are accepted in China for products available in this country. The WG suggests the importance of economic studies, specifically made in China.

CONCLUSION

This work provides evidence-based advice to establish a treatment algorithm in knee OA, for practical implementation in clinical practice in China.

An Insight of Co-Encapsulation Nigella sativa and Cosmos caudatus Kunth Extracts as Anti-Inflammatory Agent Through In Silico Study

This study analyzes anti-inflammatory activity from extracts of Nigella sativa and Cosmos caudatus Kunth co-encapsulated through in silico molecular docking. The LC-MS results revealed that extracts of N. sativa mostly contained thymoquinone and alpha-hederin, whereas quercetin and kaempferol were the major compounds in C. caudatus K. Nevertheless, the bioactive compounds are usually susceptible to degradation by exposure to light, heat, oxygen, which may limit its biological activity. Therefore, encapsulation is one of the promising techniques to protect bioactive compounds. Ligands were encapsulated with chitosan and sodium tripolyphosphate as wall materials. Cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) as the target enzymes were docked with a combination of these active compounds (non-encapsulated and encapsulated), using the HEX 8.0 program, and visualized using the Discovery studio visualizer software v16.1.0.15350. Interestingly, docking results of the combination of encapsulated ligands showed no interactions to COX-1 but interacted with COX-2. Therefore, co-encapsulation of extracts combinations has been suggested to act as anti-inflammatory agents targeted specifically to the COX-2 enzyme. The total energy of the encapsulated of combination of extract compounds to COX-2 were -1425.88 (mol/cal) for thymoquinone + quercetin; -1435.87 (mol/cal) for thymoquinone + kaempferol; 1175.97 (mol/cal) for quercetin + alpha hederin; -957.74 (mol/cal) for kaempferol + alpha hederin; and -283.3 (mol/cal) for diclofenac sodium, as a control NSAID drug. These suggest that encapsulated active compounds in N. sativa and C. caudatus K. have potency as a drug candidate for the selective NSAIDs category, which can be subjected to further in vitro and in vivo studies.

Poly beta amino ester coated emulsions of NSAIDs for cartilage treatment

Delivering drugs directly into cartilage is still the major challenge in the management and treatment of osteoarthritis (OA) resulting from the aneural, avascular and alymphatic nature of an articular cartilage structure. Progress has been made in the design of drug delivery systems that enhance corticosteroid uptake and retention in cartilage; however also non-steroidal anti-inflammatory drugs (NSAIDs) are prescribed for patients affected by OA and a drug delivery system specifically designed for this drug category is currently unavailable. We developed an approach based on the preparation of NSAID oil-in-water emulsions coated with poly-beta-amino-esters (PBAEs) to exploit the cartilage penetrating ability of such polymers and the high solubility of drugs in oil. These emulsions containing different NSAIDs (indomethacin, ketorolac, diclofenac and naproxen) exhibited enhanced and prolonged drug localisation not only in healthy cartilage tissues but also in early-stage OA samples. The critical role of the PBAE layer on oil droplets was established along with the retained biological activity of the drug as glycosaminoglycan (GAG) and collagen degradation induced by interleukin-1 (IL-1) was prevented by the novel technology. Oil-in-water coated emulsions are very flexible and cost-effective drug delivery systems and such an approach presented here could provide a substantial improvement in the therapeutic treatments of OA and thus patients' outcomes.

Mechanisms and Pharmaceutical Action of Lipid Nanoformulation of Natural Bioactive Compounds as Efficient Delivery Systems in the Therapy of Osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease. An objective of the nanomedicine and drug delivery systems field is to design suitable pharmaceutical nanocarriers with controllable properties for drug delivery and site-specific targeting, in order to achieve greater efficacy and minimal toxicity, compared to the conventional drugs. The aim of this review is to present recent data on natural bioactive compounds with anti-inflammatory properties and efficacy in the treatment of OA, their formulation in lipid nanostructured carriers, mainly liposomes, as controlled release systems and the possibility to be intra-articularly (IA) administered. The literature regarding glycosaminoglycans, proteins, polyphenols and their ability to modify the cell response and mechanisms of action in different models of inflammation are reviewed. The advantages and limits of using lipid nanoformulations as drug delivery systems in OA treatment and the suitable route of administration are also discussed. Liposomes containing glycosaminoglycans presented good biocompatibility, lack of immune system activation, targeted delivery of bioactive compounds to the site of action, protection and efficiency of the encapsulated material, and prolonged duration of action, being highly recommended as controlled delivery systems in OA therapy through IA administration. Lipid nanoformulations of polyphenols were tested both in vivo and in vitro models that mimic OA conditions after IA or other routes of administration, recommending their clinical application.

Expert review and recommendations for the management of acute, chronic, and neuropathic pain in Qatar

BACKGROUND

Pain management is an evolving area of expertise in Qatar. Gaps in knowledge, inadequate training for physicians and nurses, and the absence of policies/guidelines are the main barriers to effective pain management in Qatar. In addition, the use of certain pain medication, especially opioids, is highly regulated, limiting their availability in outpatient pain management. These factors are responsible for the undertreatment of pain in Qatar. This study aimed to standardize evidence-based local recommendations for pharmacological treatment of pain in Qatar.

METHODS

An expert panel of physicians from different disciplines, with experience in diagnosis and treatment of the three pain types (i.e., acute, chronic, and neuropathic), was convened for two face-to-face meetings in Doha, Qatar, on November 29, 2019, and on February 22, 2020, with subsequent virtual meetings. A literature search was performed on Medline and Google Scholar databases from inception till December 2019, and all relevant articles were selected. Based on these articles and repeated feedback from the authors, the final pain treatment protocols were developed.

RESULTS

Recommendations for the treatment of acute pain, based on pain severity, followed three approaches: acetaminophen/paracetamol or non-steroidal anti-inflammatory drugs (NSAIDs) for mild pain and moderate pain and referral to a pain specialist for severe pain. Acetaminophen/paracetamol or NSAIDs is recommended for chronic pain, and the use of opioids was strongly discouraged because of its long-term side effects. For neuropathic pain, tricyclic antidepressants or gabapentin or pregabalin or serotonin-norepinephrine reuptake inhibitors were recommended first-line agents. Non-responders must be referred to neurologists or a pain specialist.

CONCLUSION

The expert panel provides recommendations for the management of acute, chronic, and neuropathic pain based on international guidelines adapted to local practice and treatment availability in Qatar. More importantly, the panel has recommended taking extreme caution in the use of opioids for long-term management of chronic pain and to refer the patient to a pain specialist clinician as required.

A Malaysian Delphi consensus on managing knee osteoarthritis

BACKGROUND

The 2013 Malaysian Clinical Practice Guidelines on the Management of Osteoarthritis (OA) recommend a linear step-up approach to manage knee OA. However, patients with knee OA often require a multimodal approach to address OA-related pain symptoms and functional limitations. This consensus aimed to provide doctors with an updated set of evidence-based, clinical experience-guided recommendations to manage knee OA.

METHODS

A multi-speciality expert panel consisting of nine Malaysian physicians from different healthcare settings who manage a diverse OA patient population was convened. Using a combination of the ADAPTE process and modified Delphi method, the panel reviewed current evidence on the management of knee OA and synthesised a set of nine recommendations on the management of knee OA, supported by an algorithm that summarises the consensus' core messages.

RESULTS

A multimodal intervention strategy is the mainstay of OA management and the choice of any single or multimodal intervention may vary over the course of the disease. Overall, a non-pharmacological core treatment set of patient education, weight loss and exercise is recommended for all patients. When pharmacotherapy is indicated, symptomatic slow-acting drugs for osteoarthritis are recommended at the early stage of disease, and they can be paired with physical therapy as background treatment. Concurrent advanced pharmacotherapy that includes non-steroidal anti-inflammatory drugs, intraarticular injections and short-term weak opioids can be considered if patients do not respond sufficiently to background treatment. Patients with severe symptomatic knee OA should be considered for knee replacement surgery. Management should begin with specific treatments with the least systemic exposure or toxicity, and the choice of treatment should be determined as a shared decision between patients and their team of healthcare providers.

CONCLUSIONS

This consensus presents nine recommendations that advocate an algorithmic approach in the management of patients living with knee OA. They are applicable to patients receiving treatment from primary to tertiary care providers in Malaysia as well as other countries.

Diacerein-Loaded Hyaluosomes as a Dual-Function Platform for Osteoarthritis Management via Intra-Articular Injection: In Vitro Characterization and In Vivo Assessment in a Rat Model

The application of intra-articular injections in osteoarthritis management has gained great attention lately. In this work, novel intra-articular injectable hyaluronic acid gel-core vesicles (hyaluosomes) loaded with diacerein (DCN), a structural modifying osteoarthritis drug, were developed. A full factorial design was employed to study the effect of different formulation parameters on the drug entrapment efficiency, particle size, and zeta potential. Results showed that the prepared optimized DCN- loaded hyaluosomes were able to achieve high entrapment (90.7%) with a small size (310 nm). The morphology of the optimized hyaluosomes was further examined using TEM, and revealed spherical shaped vesicles with hyaluronic acid in the core. Furthermore, the ability of the prepared DCN-loaded hyaluosomes to improve the in vivo inflammatory condition, and deterioration of cartilage in rats (injected with antigen to induce arthritis) following intra-articular injection was assessed, and revealed superior function on preventing cartilage damage, and inflammation. The inflammatory activity assessed by measuring the rat’s plasma TNF-α and IL-1b levels, revealed significant elevation in the untreated group as compared to the treated groups. The obtained results show that the prepared DCN-loaded hyaluosomes would represent a step forward in the design of novel intra articular injection for management of osteoarthritis.

2019 revised algorithm for the management of knee osteoarthritis: the Southeast Asian viewpoint

Background

Since 2014, the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) algorithm for the management of knee osteoarthritis (OA) is available worldwide.

Aim

Based on this document, a Southeast Asia Working Group (SEAWG) wished to see how the new ESCEO algorithm developed in 2019 was perceived by Southeast Asian experts and how it was integrated into their clinical practice.

Methods

A SEAWG was set up between members of the international ESCEO task force and a group of Southeast Asian experts.

Results

Non-pharmacological management should always be combined with pharmacological management. In step 1, symptomatic slow-acting drugs for osteoarthritis are the main background therapy, for which high-quality evidence is available only for the formulations of patented crystalline glucosamine sulfate and chondroitin sulfate. In step 2, oral NSAIDs are a useful option, considering the cardiovascular/renal/gastrointestinal profiles of the individual patient. Intra-articular hyaluronic acid and corticosteroids are a possible alternative to oral NSAIDs, but limited evidence is available. If steps 1 and 2 do not give adequate relief of symptoms, tramadol can be used, but its safety is debated. In general, the indications of the ESCEO algorithm are important in Southeast Asian countries, but the reimbursement criteria of local health systems are an important aspect for adherence to the ESCEO algorithm.

Conclusion

This guidance provides evidence-based and easy-to-follow advice on how to establish a treatment algorithm in knee OA, for practical implementation in clinical practice in Southeast Asian countries.

Leaves of Cleome amblyocarpa Barr. And Murb. And Cleome arabica L.: Assessment of nutritional composition and chemical profile (LC-ESI-MS/MS), anti-inflammatory and analgesic effects of their extracts

ETHNOPHARMACOLOGICAL RELEVANCE

The Cleomaceae family is known for its richness in secondary metabolites and different Cleome species are used in folk medicine. Cleome amblyocarpa and Cleome arabica are medicinal herbs used in Tunisia and other North Africa countries to treat various diseases such as diabetes, rheumatism, colic, pain and digestive disorders.

AIM OF THE STUDY

To our knowledge, few data are available about the nutritional value, phytochemical components and biological effects of C. arabica and C. amblyocarpa cultivated in Tunisia. For this reason, the present survey aimed to determine the nutritional value, bioactive compounds and pharmacological properties of the leaves of these two species of Cleome.

MATERIALS AND METHODS

To characterize and determine the bioactive compounds in both extracts of leaves of Cleome species, ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) was used. The various nutritional parameters were analyzed, in particular the amounts of protein, carbohydrates, ash, fiber, and total lipids. Vitamin E and fatty acid profiles were also evaluated by HPLC-DAD-FLD and GC-FID, respectively. The acute toxic effects of leaf extracts in mice at concentrations of 100, 500 and 800 mg/kg body weight have been investigated. The anti-inflammatory effect of leaves extracts was examined by means of the in vitro and in vivo models. The in vivo anti-inflammatory test was assessed by means of the carrageenan induced paw edema in rats. For the in vitro anti-inflammatory assay, the red blood cells membrane stabilization and protein denaturation methods were employed. The analgesic effect of hydroalcoholic extracts of leaves was also assessed by acetic acid induced writhing model in mice.

RESULTS

The phytochemical composition and the nutritional values of the leaves of C. amblyocarpa and C. arabica were determined. Our results revealed that the leaves of C. amblyocarpa are rich in flavonoids and glucosinolates. On the other hand, these latter metabolites are not present in the C. arabica extract and the leaves are characterized by the presence of flavones, methoxyflavones and their glycosides. Our findings revealed that the leaves of the two species contain a potential quantity of vitamins; proteins, carbohydrates and dietary fiber, and their hydroalcoholic extracts indicated substantial anti-inflammatory and antinociceptive activities in all the tests. Additionally, the data from the acute toxicity test proved that the leaf extracts did not cause any mortality or signs of toxicity in animals at doses up to 800 mg/kg CONCLUSIONS: The results obtained in this investigation demonstrated that the leaves of C. arabica and C. amblyocarpa are a valuable source of nutrients and active substances. Our observations support the traditional utilize of these two Cleome species for the treatment of painful diseases and as a source of natural anti-inflammatory agents.

Biomaterial strategies for improved intra-articular drug delivery

Osteoarthritis (OA) is a joint degenerative disease that has become one of the leading causes of disability in the world. It is estimated that OA affects 50 million adults in the United States. Currently, there are no FDA-approved treatments that slow OA progression and its treatment is limited to pain management strategies and life style changes. Despite the discovery of several disease-modifying OA drugs (DMOADs) and promising results in preclinical studies, their clinical translation has been significantly limited because of poor intra-articular (IA) bioavailability and challenges in delivering these compounds to tissues of interest within the joint. Here, we review current OA treatments and their effectiveness at reducing joint pain, as well as novel targets for OA treatment and the challenges related to their clinical translation. Moreover, we discuss intra-articular (IA) drug delivery as a promising route of administration, describe its inherent challenges, and review recent advances in biomaterial-based IA drug delivery for OA treatment. Finally, we highlight the potential of tissue targeting in the development of effective IA drug delivery systems.

An international, multicentre, double-blind, randomized study (DISSCO): effect of diacerein vs celecoxib on symptoms in knee osteoarthritis

OBJECTIVE

The objective of this study was to investigate whether diacerein has comparable efficacy with celecoxib in pain reduction for treatment in symptomatic knee OA patients.

METHODS

This randomized double-blind multicentre non-inferiority trial evaluated diacerein vs celecoxib treatment in patients with Kellgren-Lawrence grade 2-3 and pain scoring ≥4 (10-cm VAS). Patients were randomized to 6 months of treatment with diacerein 50 mg (n = 187) once daily for 1 month and twice daily thereafter, or celecoxib 200 mg (n = 193) once daily. The primary outcome was the change in WOMAC pain score (0-50 cm) at 6 months, and the secondary outcomes were WOMAC sub-scores, VAS pain score, and the OMERACT-OARSI responder rate.

RESULTS

In the per protocol population, the adjusted mean change from baseline in the WOMAC pain score was -11.1 ( 0.9) with diacerein (n = 140) and -11.8 (0.9) with celecoxib (n = 148). The intergroup difference was 0.7 (95% CI: -1.8, 3.2; P = 0.597), meeting the non-inferiority margin. Supportive analysis of the intention-to-treat population gave similar results. Other outcomes showed no significant difference between treatment groups. The incidence of treatment-related adverse events was low and balanced between groups, but a greater incidence of diarrhoea occurred with diacerein (10.2% vs 3.7%). Diarrhoea was considered mild-to-moderate in all but one case with complete resolution.

CONCLUSIONS

Diacerein was non-inferior to celecoxib in reducing knee OA pain and improving physical function. Diacerein also demonstrated a good safety profile.

TRIAL REGISTRATION

A multicentre study on the effect of DIacerein on Structure and Symptoms vs Celecoxib in Osteoarthritis is a National Institutes of Health (NCT02688400) and European Clinical Trial Database (2015-002933-23) registered phase III (Canada) or IV (Europe) study.