Recent developments in the treatment of osteoarthritis with NSAIDs

Distinct characteristics of the gut virome in patients with osteoarthritis and gouty arthritis

BACKGROUND/PURPOSE(S)

The gut microbiota and its metabolites play crucial roles in pathogenesis of arthritis, highlighting gut microbiota as a promising avenue for modulating autoimmunity. However, the characterization of the gut virome in arthritis patients, including osteoarthritis (OA) and gouty arthritis (GA), requires further investigation.

METHODS

We employed virus-like particle (VLP)-based metagenomic sequencing to analyze gut viral community in 20 OA patients, 26 GA patients, and 31 healthy controls, encompassing a total of 77 fecal samples.

RESULTS

Our analysis generated 6819 vOTUs, with a considerable proportion of viral genomes differing from existing catalogs. The gut virome in OA and GA patients differed significantly from healthy controls, showing variations in diversity and viral family abundances. We identified 157 OA-associated and 94 GA-associated vOTUs, achieving high accuracy in patient-control discrimination with random forest models. OA-associated viruses were predicted to infect pro-inflammatory bacteria or bacteria associated with immunoglobulin A production, while GA-associated viruses were linked to Bacteroidaceae or Lachnospiraceae phages. Furthermore, several viral functional orthologs displayed significant differences in frequency between OA-enriched and GA-enriched vOTUs, suggesting potential functional roles of these viruses. Additionally, we trained classification models based on gut viral signatures to effectively discriminate OA or GA patients from healthy controls, yielding AUC values up to 0.97, indicating the clinical utility of the gut virome in diagnosing OA or GA.

CONCLUSION

Our study highlights distinctive alterations in viral diversity and taxonomy within gut virome of OA and GA patients, offering insights into arthritis etiology and potential treatment and prevention strategies.

Yaobitong capsules reshape and rebalance the gut microbiota and metabolites of arthritic rats: An integrated study of microbiome and fecal metabolomics analysis

Yaobitong capsule (YBTC), a Chinese medicine compound preparation, has been demonstrated to affect multiple pathways associated with inflammation and exhibit potential anti-arthritis effect. In this study, an integrated omic approach based on UHPLC-Q-TOF MS and 16S rRNA sequencing analyses was proposed to reveal the anti-arthritis effect and possible mechanism of YBTC. The AIA rat model showed that YBTC significantly alleviated the typical symptoms of AIA rats such as weight, spleen index and pro-inflammatory cytokines. Fecal metabolomics results identified 41 differential metabolites, which mainly referred to tryptophan, bile acid and fatty acid metabolism. The gut microbiota played a crucially important role in anti-inflammatory immunity, 16S rRNA results indicated that YBTC changed the community structure and alleviated the microecological imbalance caused by rheumatoid arthritis (RA). Further ROC curve analysis demonstrated that it was reliable to identify RA by using 5 metabolites and 3 microorganisms (AUC > 0.83). In summary, it was the first time that the preventive effect of YBTC in RA was confirmed. The secretion of the microbiota-mediated metabolites was significantly improved by YBTC, through its callback effect on the disturbed gut microbiota. Thus, we have indicated a potential novel strategy for the prevention of RA via evaluation of intervention effects of YBTC on AIA rat model.

Danshensu inhibits the IL-1β-induced inflammatory response in chondrocytes and osteoarthritis possibly via suppressing NF-κB signaling pathway

Purpose

Osteoarthritis (OA) is the most common inflammatory disease associated with pain and cartilage destruction. Interleukin (IL)-1β is widely used to induce inflammatory response in OA models. This study aimed to explore the role of Danshensu (DSS) in IL-1β-induced inflammatory responses in OA.

Methods

IL-1β was used to induce chondrocyte inflammation. Cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay. IL-6, COX-2, TNF-α, and iNOS mRNA levels were detected by qRT-PCR. MMP3, MMP13, ADAMTS4, ADAMTS5, Aggrecan, Collagen, p-IκBα, and p-p65 protein levels were detected by Western blot. An OA mouse model was established by surgical destabilization of the medial meniscus (DMM), and the Osteoarthritis Research Society International (OARSI) score was evaluated by H&E staining.

Results

DSS did not affect the levels of inflammatory indicators including IL-6, COX-2, TNF-α, iNOS, PEG2, and NO but suppressed COX-2 and iNOS protein expression in IL-1β treated chondrocytes. In addition, DSS downregulated IL-1β-enhanced expression of MMP3, MMP13, ADAMTS4, and ADAMTS5 and upregulated aggrecan and collagen expression. Moreover, DSS significantly inhibited IL-1β-induced phosphorylation of p-IκBα and p-p65 in a dose-dependent manner in chondrocytes, suggesting it plays a role in the NF-κB signaling pathway. Furthermore, DSS significantly reduced DMM-induced cartilage OARSI score in mice, further demonstrating its protective role in OA progression in vivo.

Conclusions

Our study revealed the protective role of DSS in OA, suggesting that DSS might act as a potential treatment for OA.

Omega-3 polyunsaturated fatty acids as an angelus custos to rescue patients from NSAID-induced gastroduodenal damage

Nonsteroidal anti-inflammat ory drugs (NSAIDs) are one of the drug types frequently prescribed for their analgesic, anti-inflammatory, and antithrombotic actions, but carry a risk of major gastroduodenal damage from mild erosive changes to serious ulceration leading to fatal outcomes. From the long history of willow tree bark and its extracts being applied for the relief of pain and fever, the synthesis of acetylsalicylic acid, the development of selective cyclooxygenase 2 inhibitors (coxibs), and the identification of a G-protein-coupled receptor for prostaglandin, the popular combination regimen of an NSAID and a proton pump inhibitor was invented, but development was continued for further improvement. With regard to major NSAID adverse effects, gastrointestinal (GI) and cardiovascular (CV) risks still remained as problems to be solved. In this review, it is shown that n-3 polyunsaturated fatty acid (PUFA) based NSAIDs can be an angelus custos, supported with facts that an intake of essential n-3 PUFAs orchestrates concerted protective actions against two notorious side effects of NSAIDs, the aforementioned GI risk and CV risk of NSAIDs. Since pills containing n-3 PUFAs, omega-3-acid ethyl ester capsules (Lovaza, Omarcor), have already been safely prescribed to prevent atherosclerosis through lessening lipid burdening, the introduction of a drug delivery system such as a gastroretentive form of n-3 PUFA based NSAIDs will highlight newer hope for GI safety under the guarantee of reduced CV risk. Because n-3 PUFAs have been proven to attenuate cytotoxicity, inhibit lipid-raft-associated harmful signaling, and relieve oxidative stress relevant to NSAIDs, n-3 PUFA based NSAIDs will be next-generation GI-safe NSAIDs.

Low-dose SoluMatrix diclofenac : a review of safety across two Phase III studies in patients with acute and osteoarthritis pain

INTRODUCTION

Similar to other NSAIDs, diclofenac is associated with serious dose-related cardiovascular, gastrointestinal, and renal adverse events. Low-dose SoluMatrix diclofenac , containing submicron particles of diclofenac, was developed to provide effective analgesia at lower drug doses compared with currently available NSAIDs.

AREAS COVERED

The efficacy and safety of low-dose SoluMatrix diclofenac was evaluated in two randomized, placebo-controlled Phase III studies: a study in patients with acute pain following bunionectomy surgery and a study in patients with osteoarthritis pain of the hip or knee. In this review article, we summarize safety data from these studies.

EXPERT OPINION

The safety results from the Phase III studies indicate that all dosing regimens of low-dose SoluMatrix diclofenac up to 12 weeks are generally well tolerated. Few serious gastrointestinal, cardiovascular, renal, or hepatic adverse events commonly associated with NSAID use were reported in these studies. Although not directly compared, the safety of SoluMatrix diclofenac was similar to findings for other diclofenac drug products. The potential for safe and effective management of acute and chronic pain at reduced NSAID doses is attractive; definitive characterization of SoluMatrix diclofenac safety requires confirmation by long-term studies.

Naproxen-induced Ca2+ movement and death in MDCK canine renal tubular cells

Naproxen is an anti-inflammatory drug that affects cellular calcium ion (Ca(2+)) homeostasis and viability in different cells. This study explored the effect of naproxen on [Ca(2+)](i) and viability in Madin-Darby canine kidney cells (MDCK) canine renal tubular cells. At concentrations between 50 μM and 300 μM, naproxen induced [Ca(2+)](i) rises in a concentration-dependent manner. This Ca(2+) signal was reduced partly when extracellular Ca(2+) was removed. The Ca(2+) signal was inhibited by a Ca(2+) channel blocker nifedipine but not by store-operated Ca(2+) channel inhibitors (econazole and SKF96365), a protein kinase C (PKC) activator phorbol 12-myristate 13-acetate, and a PKC inhibitor GF109203X. In Ca(2+)-free medium, pretreatment with 2,5-di-tert-butylhydroquinone or thapsigargin, an inhibitor of endoplasmic reticulum Ca(2+) pumps, partly inhibited naproxen-induced Ca(2+) signal. Inhibition of phospholipase C with U73122 did not alter naproxen-evoked [Ca(2+)](i) rises. At concentrations between 15 μM and 30 μM, naproxen killed cells in a concentration-dependent manner, which was not reversed by prechelating cytosolic Ca(2+) with the acetoxymethyl ester of 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl. Annexin V/propidium iodide staining data suggest that naproxen induced apoptosis. Together, in MDCK renal tubular cells, naproxen induced [Ca(2+)](i) rises by inducing Ca(2+) release from multiple stores that included the endoplasmic reticulum and Ca(2+) entry via nifedipine-sensitive Ca(2+) channels. Naproxen induced cell death that involved apoptosis.

Pharmacokinetics and safety of low-dose submicron indomethacin 20 and 40 mg compared with indomethacin 50 mg

INTRODUCTION

Indomethacin is a potent analgesic that, similar to other nonsteroidal anti-inflammatory drugs, is associated with serious dose-related adverse events. There is a need for newer nonsteroidal anti-inflammatory drug products with improved tolerability. Low-dose submicron indomethacin was developed using SoluMatrix Fine Particle Technology™ to enable treatment at lower doses than commercially available indomethacin drug products. This study evaluated the pharmacokinetics and safety of submicron indomethacin 20 and 40 mg compared with indomethacin 50-mg capsules.

METHODS

This was a phase 1, randomized, open-label, 4-period, 4-sequence, single-dose crossover study. Forty healthy volunteers received low-dose submicron indomethacin 20- or 40-mg capsules, or indomethacin 50-mg capsules under fasting or fed conditions. Pharmacokinetic parameters and safety were assessed.

RESULTS

Comparable fasting peak plasma levels (mean ± standard deviation) were demonstrated for submicron indomethacin 40 mg (2368.79 ± 631.38 ng/ml) and indomethacin 50 mg (2369.40 ± 969.06 ng/ml). The overall systemic exposure (geometric least squares mean; 95% CI) was > 21% lower for submicron indomethacin 40 mg (6007.71 ng·h/mL; 5585.73-6461.58) compared with indomethacin 50 mg (7646.23 ng·h/ml; 7110.44-8222.40) under fasting conditions. Food delayed the rate but did not affect the extent of indomethacin absorption from submicron indomethacin 40 mg. Submicron indomethacin 40 mg administration resulted in earlier time to peak plasma levels (median 1.67; min-max 0.5-3.5 hours) under fasting conditions compared with indomethacin 50 mg (2.02; 0.5-5.0 hours). Submicron indomethacin 20 and 40 mg were dose proportional and generally well tolerated.

CONCLUSION

Compared with indomethacin 50 mg, submicron indomethacin 40 mg achieved similar peak plasma concentrations, lower systemic exposure, and a faster time to peak plasma concentration, indicating rapid absorption. The current formulation of low-dose submicron indomethacin has recently demonstrated efficacy in 2 phase 3 studies in patients with acute pain following bunionectomy and represents a new, low-dose treatment option for patients with acute pain.

Efficacy and safety of ginger in osteoarthritis patients: a meta-analysis of randomized placebo-controlled trials

The aim of this study was to assess the clinical efficacy and safety of oral ginger for symptomatic treatment of osteoarthritis (OA) by carrying out a systematic literature search followed by meta-analyses on selected studies. Inclusion criteria were randomized controlled trials (RCTs) comparing oral ginger treatment with placebo in OA patients aged >18 years. Outcomes were reduction in pain and reduction in disability. Harm was assessed as withdrawals due to adverse events. The efficacy effect size was estimated using Hedges' standardized mean difference (SMD), and safety by risk ratio (RR). Standard random-effects meta-analysis was used, and inconsistency was evaluated by the I-squared index (I(2)). Out of 122 retrieved references, 117 were discarded, leaving five trials (593 patients) for meta-analyses. The majority reported relevant randomization procedures and blinding, but an inadequate intention-to-treat (ITT) analysis. Following ginger intake, a statistically significant pain reduction SMD = -0.30 ([95% CI: [(-0.50, -0.09)], P = 0.005]) with a low degree of inconsistency among trials (I(2) = 27%), and a statistically significant reduction in disability SMD = -0.22 ([95% CI: ([-0.39, -0.04)]; P = 0.01; I(2) = 0%]) were seen, both in favor of ginger. Patients given ginger were more than twice as likely to discontinue treatment compared to placebo ([RR = 2.33; 95% CI: (1.04, 5.22)]; P = 0.04; I(2) = 0%]). Ginger was modestly efficacious and reasonably safe for treatment of OA. We judged the evidence to be of moderate quality, based on the small number of participants and inadequate ITT populations. Prospero: CRD42011001777.

Efficacy and safety of low-dose submicron diclofenac for the treatment of osteoarthritis pain: a 12 week, phase 3 study

OBJECTIVE

NSAIDs, such as diclofenac, are the most commonly used medications to treat osteoarthritis (OA), but they are associated with dose-related adverse events (AEs). Low-dose submicron diclofenac was developed using a new, proprietary dry milling process that creates submicron drug particles (SoluMatrix Fine Particle Technology * ), enabling effective treatment at lower doses than other commercially available diclofenac drug products. This phase 3 study evaluated the efficacy and safety of low-dose submicron diclofenac 35 mg three times daily (tid) and twice daily (bid) in patients with OA pain.

RESEARCH DESIGN AND METHODS

This double-blind study enrolled patients ≥40 years of age with clinically and radiographically confirmed (Kellgren-Lawrence grade II-III) hip or knee OA. Eligible patients were chronic NSAID and/or acetaminophen (APAP) users with baseline Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) pain subscale scores ≥40 mm by visual analog scale and an OA flare (≥15 mm increase in WOMAC pain subscale score following discontinuation of NSAIDs/APAP at screening). Patients were randomized to submicron diclofenac 35 mg tid, submicron diclofenac 35 mg bid, or placebo for 12 weeks. ClinicalTrials.gov identifier: NCT01461369.

MAIN OUTCOME MEASURES

Efficacy parameters included mean change from baseline in WOMAC pain subscale score at week 12 (primary efficacy parameter) and in average total WOMAC score over 12 weeks.

RESULTS

Submicron diclofenac 35 mg tid significantly improved WOMAC pain subscale scores from baseline at 12 weeks (-44.1; p = 0.0024) compared with placebo (-32.5). Submicron diclofenac 35 mg bid provided numerical improvement in pain at week 12 that did not reach statistical significance (-39.0; p = 0.0795) compared with placebo. Submicron diclofenac 35 mg tid (-35.9; p = 0.0002) and 35 mg bid (-30.3; p = 0.0363) improved the average total WOMAC score in treated patients over 12 weeks compared with placebo (-23.2). The most frequent AEs in the submicron diclofenac-treated groups were diarrhea, headache, nausea, and constipation. The inclusion of patients with a documented requirement for analgesic therapy (OA 'flare') at baseline and the high rates of rescue medication usage in the placebo group may have impacted the study outcome for the submicron diclofenac treatment groups.

CONCLUSIONS

Low-dose submicron diclofenac is an effective therapeutic option for the treatment of OA pain.

Complexities in the pharmacologic management of osteoarthritis pain

OBJECTIVE

To discuss challenges in the pharmacologic management of osteoarthritis (OA) pain.

SCOPE

Literature searches through MEDLINE and Cochrane databases were used to identify relevant journal articles. The search was limited to articles published from January 1982 to January 2013. Additional references were obtained from articles extracted during the database search.

FINDINGS

Pharmacologic management of OA is aimed at alleviating pain and reducing functional impairment. Limitations of the most commonly prescribed agents (non-steroidal anti-inflammatory drugs [NSAIDs], acetaminophen, and opioids) and conflicting practice guidelines have led to physician and patient dissatisfaction. OA management guidelines advocate the use of acetaminophen, NSAIDs, serotonin-norepinephrine reuptake inhibitors (SNRIs) and opioids; however, these agents are associated with serious adverse events (AEs) and, in some cases, efficacy concerns. Acetaminophen, particularly at higher dosages, may lead to acute liver failure and gastrointestinal (GI) bleeding. NSAIDs present a significant GI bleeding risk and are also associated with a variety of renal complications, myocardial infarction and other serious cardiovascular complications. SNRIs can cause AEs such as hepatotoxicity and drug/drug interactions that can lead to serotonin syndrome. Opioids exhibit abuse potential and tramadol may demonstrate limited efficacy.

CONCLUSIONS

The safety and efficacy concerns associated with currently available OA treatment options establish a need to develop new treatment strategies. Disease-modifying agents and novel drug formulations are currently under investigation. As these new pharmacologic options evolve, their adoption may lower risk and improve clinical outcomes.

High-density cell systems incorporating polymer microspheres as microenvironmental regulators in engineered cartilage tissues

To address the significant clinical need for tissue-engineered therapies for the repair and regeneration of articular cartilage, many systems have recently been developed using bioactive polymer microspheres as regulators of the chondrogenic microenvironment within high-density cell cultures. In this review, we highlight various densely cellular systems utilizing polymer microspheres as three-dimensional (3D) structural elements within developing engineered cartilage tissue, carriers for cell expansion and delivery, vehicles for spatiotemporally controlled growth factor delivery, and directors of cell behavior via regulation of cell-biomaterial interactions. The diverse systems described herein represent a shift from the more traditional tissue engineering approach of combining cells and growth factors within a biomaterial scaffold, to the design of modular systems that rely on the assembly of cells and bioactive polymer microspheres as building blocks to guide the creation of articular cartilage. Cell-based assembly of 3D microsphere-incorporated structures represents a promising avenue for the future of tissue engineering.