Gubi decoction mitigates knee osteoarthritis via promoting chondrocyte autophagy through METTL3-mediated ATG7 m6A methylation

Knee osteoarthritis (KOA) is a chronic joint disease that significantly affects the health of the elderly. As an herbal remedy, Gubi decoction (GBD) has been traditionally used for the treatment of osteoarthritis-related syndromes. However, the anti-KOA efficacy and mechanism of GBD remain unclear. This study aimed to experimentally investigate the anti-KOA efficacy and the underlying mechanism of GBD. The medial meniscus (DMM) mice model and IL-1β-stimulated chondrocytes were, respectively, constructed as in vivo and in vitro models of KOA to evaluate the osteoprotective effect and molecular mechanism of GBD. The UPLC-MS/MS analysis showed that GBD mainly contained pinoresinol diglucoside, rehmannioside D, hesperidin, liquiritin, baohuoside I, glycyrrhizic acid, kaempferol and tangeretin. Animal experiment showed that GBD could alleviate articular cartilage destruction and recover histopathological alterations in DMM mice. In addition, GBD inhibited chondrocyte apoptosis and restored DMM-induced dysregulated autophagy evidenced by the upregulation of ATG7 and LC3 II/LC3 I but decreased P62 level. Mechanistically, METTL3-mediated m6A modification decreased the expression of ATG7 in DMM mice, as it could be significantly attenuated by GBD. METTL3 overexpression significantly counteracted the protective effect of GBD on chondrocyte autophagy. Further research showed that GBD promoted proteasome-mediated ubiquitination degradation of METLL3. Our findings suggest that GBD could act as a protective agent against KOA. The protective effect of GBD may result from its promotion on chondrocyte autophagy by suppressing METTL3-dependent ATG7 m6A methylation.

Analgesic prescribing in patients with inflammatory arthritis in England: observational studies in the Clinical Practice Research Datalink

OBJECTIVES

Despite little evidence that analgesics are effective in inflammatory arthritis (IA), studies report substantial opioid prescribing. The extent this applies to other analgesics is uncertain. We undertook a comprehensive evaluation of analgesic prescribing in patients with IA in the Clinical Practice Research Datalink Aurum to evaluate this.

METHODS

From 2004 to 2020, cross-sectional analyses evaluated analgesic prescription annual prevalence in RA, PsA and axial spondyloarthritis (axSpA), stratified by age, sex, ethnicity, deprivation and geography. Joinpoint regression evaluated temporal prescribing trends. Cohort studies determined prognostic factors at diagnosis for chronic analgesic prescriptions using Cox proportional hazards models.

RESULTS

Analgesic prescribing declined over time but remained common: 2004 and 2020 IA prescription prevalence was 84.2/100 person-years (PY) (95% CI 83.9, 84.5) and 64.5/100 PY (64.2, 64.8), respectively. In 2004, NSAIDs were most prescribed (56.1/100 PY; 55.8, 56.5), falling over time. Opioids were most prescribed in 2020 (39.0/100 PY; 38.7, 39.2). Gabapentinoid prescribing increased: 2004 prevalence 1.1/100 PY (1.0, 1.2); 2020 prevalence 9.9/100 PY (9.7, 10.0). Most opioid prescriptions were chronic (2020 prevalence 23.4/100 PY [23.2, 23.6]). Non-NSAID analgesic prescribing was commoner in RA, older people, females and deprived areas/northern England. Conversely, NSAID prescribing was commoner in axSpA/males, varying little by deprivation/geography. Peri-diagnosis was high-risk for starting chronic opioid/NSAID prescriptions. Prognostic factors for chronic opioid/gabapentinoid and NSAID prescriptions differed, with NSAIDs having no consistently significant association with deprivation (unlike opioids/gabapentinoids).

CONCLUSION

IA analgesic prescribing of all classes is widespread. This is neither evidence-based nor in line with guidelines. Peri-diagnosis is an opportune moment to reduce chronic analgesic prescribing.

Cohort study investigating gout flares and management in UK general practice

BACKGROUND

Gout is the most common inflammatory arthritis and is almost exclusively managed in primary care, however the course and severity of the condition is variable and poorly characterised. This research aims improve understanding about the frequency of, and factors associated with, gout flares in the UK and characterise the factors associated with the initiation of ULT.

METHODS

Using the Clinical Practice Research Database, patients with a coded incident gout diagnosis without a prior prescription for urate-lowering therapy (ULT) were identified. Gout flares post diagnosis and ULT initiation were identified through prescribing and coded data. Patient characteristics, co-morbidities and co-prescribing were co-variants. Factors associated with gout flares and ULT initiation were analysed using cox-proportional hazard model and logistic regression.

RESULTS

Fifty-one thousand seven hundred eighty-four patients were identified: 18,605 (35.9%, 95%CI 35.5-36.3%) had experienced ≥ 1 recurrent flare, 17.4% (95%CI 17.1-17.8%) within 12 months of diagnosis. Male sex, black ethnicity, higher BMI, heart failure, CKD, CVD and diuretic use were associated with flares, with the highest HR seen with high serum urate levels (≥ 540 µmol/L HR 4.63, 95%CI 4.03-5.31). ULT initiation was associated with similar variables, although higher alcohol intake and older age were associated with lower odds of ULT initiation but were not associated with flares. ULT was initiated in 27.7% (95%CI 27.3-28.0%): 5.7% (95%CI 5.5-5.9%) within 12 months of diagnosis. ULT initiation rates were higher in patients with recurrent flares.

CONCLUSION

Approximately one in six people with incident gout had a second flare within 12 months. Factors associated with flare recurrence and ULT initiation were similar, but ULT initiation occurred later after diagnosis than previously thought.

Interactions of Nonsteroidal Antiinflammatory Drugs and Aspirin and Risk of Cardiovascular Disease in Patients With Osteoarthritis

Nonsteroidal antiinf lammatory drugs (NSAIDs) remain the mainstay of the pharmacologic management for relieving osteoarthritis pain, and low-dose aspirin is often prescribed to osteoarthritis patients who are at high risk of cardiovascular disease (CVD). We conducted cohort studies using data from The Health Improvement Network (THIN) database (2000-2019) to assess whether the relationship of initiation of naproxen or ibuprofen vs. initiation of other NSAIDs (excluding both naproxen and ibuprofen), respectively, to the risk of CVD was modified by coprescription of low-dose aspirin among the participants with osteoarthritis. Among participants without coprescription of aspirin, the risk of CVD was lower in naproxen initiators (10.3/1000 person-years) than in other NSAIDs initiators (13.2/1000 person-years; hazard ratio = 0.71, 95% confidence interval: 0.60, 0.85). Among participants with coprescription of aspirin, however, the risk of CVD was higher among naproxen initiators (36.9/1000 person-years) than that among other NSAIDs initiators (34.8/1000 person-years; hazard ratio = 1.48, 95% confidence interval: 1.12, 1.84). The association was significantly modified by coprescription of aspirin (P < 0.001). Similar findings were observed in the association of initiation of ibuprofen vs. other NSAIDs with the risk of CVD, which was significantly modified by coprescription of aspirin (P < 0.001). These findings suggest that osteoarthritis patients and clinicians should be aware of the potential CVD risk of concurrently taking naproxen or ibuprofen and low-dose aspirin.

Comparative efficacy of exercise therapy and oral non-steroidal anti-inflammatory drugs and paracetamol for knee or hip osteoarthritis: a network meta-analysis of randomised controlled trials

OBJECTIVE

Clinical guidelines recommend exercise as a core treatment for knee or hip osteoarthritis (OA). However, how its analgesic effect compares to analgesics, for example, oral non-steroidal anti-inflammatory drugs (NSAIDs) and paracetamol-the most commonly used analgesics for OA, remains unknown.

DESIGN

Network meta-analysis.

DATA SOURCES

PubMed, Embase, Scopus, Cochrane Library and Web of Science from database inception to January 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials (RCTs) comparing exercise therapy with oral NSAIDs and paracetamol directly or indirectly in knee or hip OA.

RESULTS

A total of n=152 RCTs (17 431 participants) were included. For pain relief, there was no difference between exercise and oral NSAIDs and paracetamol at or nearest to 4 (standardised mean difference (SMD)=-0.12, 95% credibility interval (CrI) -1.74 to 1.50; n=47 RCTs), 8 (SMD=0.22, 95% CrI -0.05 to 0.49; n=2 RCTs) and 24 weeks (SMD=0.17, 95% CrI -0.77 to 1.12; n=9 RCTs). Similarly, there was no difference between exercise and oral NSAIDs and paracetamol in functional improvement at or nearest to 4 (SMD=0.09, 95% CrI -1.69 to 1.85; n=40 RCTs), 8 (SMD=0.06, 95% CrI -0.20 to 0.33; n=2 RCTs) and 24 weeks (SMD=0.05, 95% CrI -1.15 to 1.24; n=9 RCTs).

CONCLUSIONS

Exercise has similar effects on pain and function to that of oral NSAIDs and paracetamol. Given its excellent safety profile, exercise should be given more prominence in clinical care, especially in older people with comorbidity or at higher risk of adverse events related to NSAIDs and paracetamol.CRD42019135166.

Pain Intensity and Trajectory Following Intra-Articular Injection of Mono-Iodoacetate in Experimental Osteoarthritis: A Meta-Analysis of In Vivo Studies

OBJECTIVE

Although most frequently used in experimental osteoarthritis (OA) pain induction, intra-articular mono-iodoacetate (MIA) injection lacks concluded references for dose selection and timing of intervention. Herein, we aimed to compare the pain intensity of rats induced by different doses of MIA and explored the trajectory of pain.

DESIGN

PubMed, Embase, and Web of Science were searched up to June 2021 for literatures involving MIA experiments investigating OA pain. Pain intensity was measured based on weightbearing distribution (WBD) and paw withdrawal thresholds (PWT), and the pain trajectory was constructed by evaluating pain intensity at a series of time points after MIA injection. A conventional meta-analysis was conducted.

RESULTS

A total of 140 studies were included. Compared with saline, MIA injections caused significantly higher pain intensity for WBD and PWT. Dose-response relationships between different doses of MIA and pain intensity were observed (P-for-trend<0.05). A pronounced increase in pain occurred from day 0 to day 7, but the uptrend ceased between day 7 and day 14, after which the pain intensity continued to rise and reached the maximum by day 28.

CONCLUSIONS

Pain intensity after intra-articular MIA injection increased in a dose-dependent manner and the pain trajectory manifested a specific pattern consistent with the pathological mechanisms of MIA-induced pain, providing possible clues for proper dose selection and timing of specific OA pain interventions.

Predictive value of gastrointestinal symptoms and patient risk factors for NSAID-associated gastrointestinal ulcers defined by endoscopy? Insights from a pooled analysis of two naproxen clinical trials

OBJECTIVE

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used to treat pain and rheumatic conditions. To facilitate patient management, we determined the predictive value of gastrointestinal (GI) symptoms and risk factors for the development of NSAID-associated GI injuries.

METHODS

Post-hoc analysis of pooled data from naproxen treatment arms of two identical, randomized, double-blind, controlled phase 3 trials in arthritis patients at risk of GI adverse events. Endoscopic incidence of GI ulcers at baseline, and 1, 3, and 6 months was employed as a surrogate parameter for GI injury. For GI symptom analysis, Severity of Dyspepsia Assessment questionnaire was used. For GI risk factor analysis, the high risk factors: previous GI injury, concomitant selective serotonin reuptake inhibitors or corticosteroids, ulcer history, concomitant low-dose aspirin, and age >65 years were employed.

RESULTS

Data of 426 naproxen patients were analyzed. Distribution of GI symptoms between patients with and without ulcer was similar; about one third of patients developing an ulcer reported no GI pain symptoms. GI symptoms experienced under naproxen treatment were thus not indicative of GI injury. The proportion of patients developing an ulcer increased with the number of risk factors present, however, about a quarter of patients without any of the analyzed risk factors still developed an ulcer.

CONCLUSION

GI symptoms and the number of risk factors are not reliable predictors of NSAID-induced GI injury to decide which patients need gastroprotection and will lead to a large group of patients with GI injuries. A preventive rather than reactive approach should be taken.

CDDO-Im ameliorates osteoarthritis and inhibits chondrocyte apoptosis in mice via enhancing Nrf2-dependent autophagy

Osteoarthritis (OA) is the most prevalent chronic degenerative joint disease with few treatment options. The pathogenesis of OA is characterized by sustained inflammation, oxidative stress and chondrocyte apoptosis that eventually lead to cartilage degradation and joint dysfunction. In the present study, we identified a synthetic triterpenoid CDDO-Im(1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl] imidazole) as an activator of Nrf2 (nuclear factor erythroid 2-related factor 2) that displayed strong anti-OA effects. We showed that CDDO-Im (20 nM) significantly alleviated TNF-α-induced apoptosis of primary human chondrocytes and extracellular matrix degradation. In a mouse OA model incurred by DMM (destabilization of medial meniscus), administration of CDDO-Im (2.5 mg/kg, ip, every other day for 8 weeks) effectively reduced knee joint cartilage erosion and serum levels of inflammatory cytokines IL-1β and IL-6. We revealed that CDDO-Im (20 nM) significantly enhanced autophagy activities in chondrocytes, whereas the autophagy inhibition by chloroquine (CQ, 50 μM) or 3-methyladenine (3-MA, 5 mM) abrogated the anti-apoptosis and chondroprotective effects of CDDO-Im in TNF-α-treated chondrocytes. Moreover, we confirmed that CDDO-Im (1-20 nM) dose-dependently activated Nrf2 pathway in TNF-α-treated chondrocytes, and its chondroprotective and autophagy-enhancing effects were significantly diminished when Nrf2 signaling was blocked by Nrf2 inhibitor ML385 (20 μM) or siRNA-mediated Nrf2 knockdown. Together, our results demonstrate that CDDO-Im exhibits prominent chondroprotective and anti-OA activities owing to its Nrf2 activation and autophagy-enhancing properties, which might provide new insights into the strategies of OA clinical prevention and treatment.

Comorbidities and use of analgesics in people with knee pain: a study in the Nottingham Knee Pain and Health in the Community (KPIC) cohort

Objectives

The aims were to examine the prevalence of comorbidities and role of oral analgesic use in people with knee pain (KP) compared with those without.

Methods

The Knee Pain and related health In the Community (KPIC) cohort comprises community-derived adults aged ≥40 years, irrespective of knee pain. Thirty-six comorbidities across 10 systems were compared between people with KP and controls without KP or knee OA. Multivariable logistic regression analysis was used to determine the adjusted odds ratio (aOR) and 95% CI for multimorbidity (at least two chronic conditions) and each specific comorbidity. Both prescribed and over-the-counter analgesics were included in the model, and their interactions with KP for comorbidity outcomes were examined.

Results

Two thousand eight hundred and thirty-two cases with KP and 2518 controls were selected from 9506 baseline participants. The mean age of KP cases was 62.2 years, and 57% were women. Overall, 29% of the total study population had multimorbidity (KP cases 34.4%; controls 23.8%). After adjustment for age, sex, BMI and analgesic use, KP was significantly associated with multimorbidity (aOR 1.35; 95% CI 1.17, 1.56) and with cardiovascular (aOR 1.25; 95% CI 1.08, 1.44), gastrointestinal (aOR 1.34; 95% CI 1.04, 1.92), chronic widespread pain (aOR 1.54; 95% CI 1.29, 1.86) and neurological (aOR 1.32; 95% CI 1.01, 1.76) comorbidities. For multimorbidity, the use of paracetamol and opioids interacted positively with KP, whereas the use of NSAIDs interacted negatively for seven comorbidities.

Conclusion

People with KP are more likely to have other chronic conditions. The long-term benefits and harms of this change remain to be investigated.

Trial registration

ClinicalTrials.gov, http://clinicaltrials.gov, NCT02098070.

Comorbidities in osteoarthritis (ComOA): a combined cross-sectional, case-control and cohort study using large electronic health records in four European countries

INTRODUCTION

Osteoarthritis (OA) is one of the leading chronic conditions in the older population. People with OA are more likely to have one or more other chronic conditions than those without. However, the temporal associations, clusters of the comorbidities, role of analgesics and the causality and variation between populations are yet to be investigated. This paper describes the protocol of a multinational study in four European countries (UK, Netherlands, Sweden and Spain) exploring comorbidities in people with OA.

METHODS AND ANALYSIS

This multinational study will investigate (1) the temporal associations of 61 identified comorbidities with OA, (2) the clusters and trajectories of comorbidities in people with OA, (3) the role of analgesics on incidence of comorbidities in people with OA, (4) the potential biomarkers and causality between OA and the comorbidities, and (5) variations between countries.A combined case-control and cohort study will be conducted to find the temporal association of OA with the comorbidities using the national or regional health databases. Latent class analysis will be performed to identify the clusters at baseline and joint latent class analysis will be used to examine trajectories during the follow-up. A cohort study will be undertaken to evaluate the role of non-steroidal anti-inflammatory drugs (NSAIDs), opioids and paracetamol on the incidence of comorbidities. Mendelian randomisation will be performed to investigate the potential biomarkers for causality between OA and the comorbidities using the UK Biobank and the Rotterdam Study databases. Finally, a meta-analyses will be used to examine the variations and pool the results from different countries.

ETHICS AND DISSEMINATION

Research ethics was obtained according to each database requirement. Results will be disseminated through the FOREUM website, scientific meetings, publications and in partnership with patient organisations.

Treating osteoarthritis pain: mechanisms of action of acetaminophen, nonsteroidal anti-inflammatory drugs, opioids, and nerve growth factor antibodies

Osteoarthritis (OA) is a common difficult-to-treat condition where the goal, in the absence of disease-modifying treatments, is to alleviate symptoms such as pain and loss of function. Acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), and opioids are common pharmacologic treatments for OA. Antibodies directed against nerve growth factor (NGF-Abs) are a new class of agents under clinical investigation for the treatment of OA. This narrative review describes (and uses schematics to visualize) nociceptive signaling, chronification of pain, and the mechanisms of action (MOAs) of these different analgesics in the context of OA-related pain pathophysiology. Further, the varying levels of efficacy and safety of these agents observed in patients with OA is examined, based on an overview of published clinical data and/or treatment guidelines (when available), in the context of differences in their MOAs.

Pain Pharmacotherapy in a Large Cohort of Patients with Osteoarthritis: A Real-World Data Analysis

INTRODUCTION

There is limited evidence on the consumption of analgesics in real-world large cohorts of patients with osteoarthritis (OA), especially in those with comorbidities. We aimed to characterize the use of pharmacological analgesic treatments, evaluate standardized comorbidity rates, and assess treatment trends. Our hypotheses were: (1) OA patients generally consume low and inconsistent pharmacological analgesic treatments; (2) analgesic treatment is often non-congruent with comorbidity-related safety concerns.

METHODS

The study was carried out at the second largest health maintenance organization in Israel. Members aged 18 years or above who were diagnosed with OA before December 31, 2018, were included. Information was obtained from the members' electronic medical record (EMR) including data on dispensed prescriptions, which were used to estimate analgesic consumption.

RESULTS

A total of 180,126 OA patients were included in our analyses; analgesics were dispensed to 64.2% of the patients, with oral NSAIDs and opioids dispensed to 34.1 and 22.9% of the OA population, respectively. Analgesic use increased with time lapsed from OA diagnosis (p < 0.001), up to a median of 59 days covered (IQR, 20-175) after 21 years. Rates of most comorbidities in the OA population were higher compared to the MHS general population. Patients with comorbidities used more NSAIDs and opioids compared to those without them.

CONCLUSIONS

Most OA patients use analgesics, usually oral NSAIDs. Analgesic use remains relatively low throughout the years, indicating that many OA patients are not being treated pharmacologically for pain on a regular basis. Despite having higher rates of several comorbidities compared to MHS general population, many OA patients are still treated with analgesics that can be associated with a worsening in comorbidity.