Treatment options for osteoarthritis: considerations for older adults

Evaluation of Biomarkers and Immune Microenvironment of Osteoarthritis: Evidence From Omics Data and Machine Learning

Objectives: This study aimed to identify novel biomarkers for osteoarthritis (OA) and explore potential pathological immune cell infiltration. Methods: We identified differentially expressed genes (DEGs) between OA and normal synovial tissues using the limma package in R, and performed enrichment analyses to understand the functions and enriched pathways of DEGs. Weighted gene co-expression network analysis (WGCNA) and distinct machine-learning algorithms were then used to identify hub modules and candidate biomarkers. We assessed the diagnostic value of the candidate biomarkers using receiver operating characteristic (ROC) analysis. We then used the CIBERSORT algorithm to analyze immune cell infiltration patterns, and the Wilcoxon test to screen out hub immune cells that might affect OA occurrence. Finally, the expression levels of hub biomarkers were confirmed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Results: We identified 102 up-regulated genes and 110 down-regulated genes. The functional enrichment analysis results showed that DEGs are enriched mainly in immune response pathways. Combining the results of the algorithms and ROC analysis, we identified GUCA1A and NELL1 as potential diagnostic biomarkers for OA, and validated their diagnosibility using an external dataset. Construction of a TF-mRNA-miRNA network enabled prediction of potential candidate compounds targeting hub biomarkers. Immune cell infiltration analyses revealed the expression of hub biomarkers to be correlated with CD8 T cells, memory B cells, M0/M2 macrophages, resting mast cells and resting dendritic cells. qRT-PCR results showed both GUCA1A and NELL1 were significantly increased in OA samples (p < 0.01). All validations are consistent with the microarray hybridization, indicating that GUCA1A and NELL1 may be involved in the pathogenesis of OA. Conclusion: The findings suggest that GUCA1A and NELL1, closely related to OA occurrence and progression, represent new OA candidate markers, and that immune cell infiltration plays a significant role in the progression of OA.

Proximal Fibular Osteotomy in the Management of Osteoarthritis of Medial Compartment of Knee Joint

Introduction: This study was conducted to evaluate the efficacy of proximal fibular osteotomy (PFO) in terms of pain relief, and improvement in function in medial compartment osteoarthritis (OA) of the knee joint.

Materials and methods: This case series study was conducted at the Shaheed Mohtarma Benazir Bhutto Medical College Lyari and United Medical and Dental College of Karachi. Patients with medial compartment knee joint OA were included in the study and patients with bicompartmental or tricompartmental OA, inflammatory joint disease, valgus knee deformity, morbid obesity, or any infectious pathology involving the knee joint were excluded from the study. The medial and lateral joint spaces were measured and recorded preoperatively and postoperatively. Pre- and postoperative values of visual analog scale (VAS) results and the Oxford knee score were recorded. A PFO was performed after getting informed written consent.

Results: A total of 60 patients were enrolled in the study; 16 (26.7%) were men, and 44 (73.3%) were women. The mean age of patients was 51.8 ± 4.1 years. The mean preoperative medial joint space measurement on standard anteroposterior radiograph was 1.45 ± 0.28 mm. The mean preoperative lateral joint space was 8.86 ± 1.27 mm. The recorded mean preoperative Oxford knee score was 20.82 ± 1.97 mm. Recorded levels of mean postoperative medial joint space improved to 4.63 ± 0.668 mm, and mean postoperative lateral joint space was 4.72 ± 0.79 mm. Mean recorded levels of VAS for pain postoperatively were 2.32 ± 0.792, which improved significantly from 7.90 ± 0.79.

Conclusions: PFO is a good surgical technique for pain relief and functional improvement in patients suffering from medial compartment OA.

Identification of Key Genes and Pathways Associated with Sex Differences in Osteoarthritis Based on Bioinformatics Analysis

Sex differences have been suggested to play critical roles in the pathophysiology of osteoarthritis (OA), resulting in sex-specific prevalence and incidence. However, their roles in the development of OA remain largely unknown. The aim of this study was to screen out key genes and pathways mediating biological differences between OA females after menopause and OA males. First, the gene expression data of GSE36700 and GSE55457 were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) between sexes were identified using R software, respectively. The overlapping DEGs were obtained. Then, protein-protein interactive (PPI) network was constructed to further analyze interactions between the overlapping DEGs. Finally, enrichment analyses were separately performed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes tools. In our results, a total of 278 overlapping DEGs were identified between OA females after menopause and OA males, including 219 upregulated and 59 downregulated genes. In the PPI network, seven hub genes were identified, including EGF, ERBB2, CDC42, PIK3R2, LCK, CBL, and STAT1. Functional enrichment analysis revealed that these genes were mainly enriched in PI3K-Akt signaling pathway, osteoclast differentiation, and focal adhesion. In conclusion, the results in the current study suggest that pathways of PI3K-Akt, osteoclast differentiation, and focal adhesion may play important roles in the development of OA females after menopause. EGFR, ERBB2, CDC42, and STAT1 may be key genes related to OA progression in postmenopausal women and may be promising therapeutic targets for OA.

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

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

Feasibility of a Randomized Controlled Trial of Self-Administered Acupressure for Symptom Management in Older Adults with Knee Osteoarthritis

OBJECTIVES

To assess the feasibility of a study to evaluate the efficacy of self-administered acupressure in pain and related symptom management for older people with symptomatic knee osteoarthritis. Feasibility with regard to (1) sample recruitment and retention, (2) treatment fidelity and adherence, and (3) tolerability and adverse events was examined.

METHODS

The study was a randomized controlled trial. Community-living older adults were recruited and randomly assigned to one of three groups: verum acupressure, sham acupressure, and usual care. Participants in the first two groups learned their respective acupressure protocol during their first center visit and from a set of materials. They were asked to practice the protocol at home once daily, 5 days a week, for 8 weeks. Participants attended three center visits and received weekly phone calls from a research assistant in an 8-week study period. Both quantitative and qualitative data collected from center visits and weekly phone calls were used to examine study feasibility.

RESULTS

A total of 150 participants (mean age, 73 years; 38% men) were enrolled; 83% completed all three center visits. Among those assigned to verum and sham acupressure groups, 94% passed a fidelity check at the second visit, more than 80% reported performing self-administered acupressure as instructed most of the time, and about 10% reported discomfort from performing the acupressure. Thirty adverse events were reported; most were related to pre-existing health conditions.

CONCLUSIONS

It is feasible to conduct a study of self-administered acupressure for symptom management in community-living older adults with knee osteoarthritis, although sample recruitment may be challenging.

Intra-articular delivery of a methotrexate loaded nanostructured lipid carrier based smart gel for effective treatment of rheumatic diseases

A nanostructured lipid carrier (NLC) based smart gel of methotrexate (MTX) was developed as a potential system for the treatment of rheumatic diseases (RD).

Knee osteoarthritis related pain: a narrative review of diagnosis and treatment

BACKGROUND

Osteoarthritis is a common progressive joint disease, involving not only the joint lining but also cartilage, ligaments, and bone. For the last ten years, majority of published review articles were not specific to osteoarthritis of the knee, and strength of evidence and clinical guidelines were not appropriately summarized.

OBJECTIVES

To appraise the literature by summarizing the findings of current evidence and clinical guidelines on the diagnosis and treatment of knee osteoarthritis pain.

METHODOLOGY

English journal articles that focused on knee osteoarthritis related pain were searched via PubMed (1 January 2002 - 26 August 2012) and Physiotherapy Evidence Database (PEDro) databases, using the terms 'knee', 'osteoarthritis' and 'pain'. In addition, reference lists from identified articles and related book chapters were included as comprehensive overviews.

RESULTS

For knee osteoarthritis, the highest diagnostic accuracy can be achieved by presence of pain and five or more clinical or laboratory criteria plus osteophytes. Some inconsistencies in the recommendations and findings were found between the clinical guidelines and systematic reviews. Generally, paracetamol, oral and topical non-steroidal anti-inflammatory drugs, opioids, corticosteroid injections and physical therapy techniques, such as therapeutic exercises, joint manual therapy and transcutaneous electrical nerve stimulation, can help reduce pain and improve function. Patient education programs and weight reduction for overweight patients are important to be considered.

CONCLUSIONS

Some inconsistencies in the recommendations and findings were found between the clinical guidelines and systematic reviews. However, it is likely that a combination of pharmacological and non-pharmacological treatments is most effective in treating patients with knee osteoarthritis.

Genes expressed in blood link osteoarthritis with apoptotic pathways

OBJECTIVE

To identify novel gene expression networks in blood of osteoarthritis patients compared to controls.

METHODS

A comprehensive exploration of gene expression in peripheral blood was performed by microarray analysis for a subset of osteoarthritis patients from the Genetics osteoARthritis and Progression (GARP) study in comparison with sex and age-matched healthy controls. To identify pathways, we performed gene enrichment analyses (database for annotation, visualisation and integrated discovery and search tool for the retrieval of interacting genes). Quantitative PCR analysis in overlapping and in additional osteoarthritis samples was performed for prioritised genes to validate and replicate findings. Classification of cases and controls was explored by applying statistical models.

RESULTS

741 probes representing 694 unique genes were differentially expressed between cases and controls, including 86 genes expressed with at least a 1.5-fold difference. ATF4, GPR18 and H3F3B were among the top genes identified (p<4.5 × 10(-8)). We found that in the blood of osteoarthritis patients the apoptosis pathway, including the well-known gene CASP3, was significantly enriched among the differentially expressed genes. Our findings were validated in independent samples and when using a small subset of the validated genes, we could accurately distinguish patients from controls (area under the curve 98%).

CONCLUSIONS

In the current study, we have identified specific gene expression networks, in the easily accessible tissue blood, which associated consistently with osteoarthritis among GARP study cases. Our data further hint at the relevance of apoptosis as an aetiological factor in osteoarthritis onset, thereby qualifying expression profiling of blood as a useful tool to understand the underlying molecular mechanisms of osteoarthritis.

Further studies on anti-inflammatory activity of maprotiline in carrageenan-induced paw edema in rat

Antidepressant drugs are commonly used for treatment of different medical disorders besides of psychiatric diseases. Accumulating evidence suggests that antidepressants exhibit anti-inflammatory activity in vivo and in vitro conditions, but the mechanisms of this property are not clear very well. In our earlier work, we demonstrated that i.c.v. and i.p. injection of maprotiline, as an antidepressant, decreased paw edema at the fourth hour after subplantar injection of carrageenan. Therefore, this work was undertaken to investigate anti-inflammatory effects of maprotiline in more details. Our results verified that i.p. (25 and 50 mg/kg) and i.c.v. (100 μg/rat) application of maprotiline significantly reduced paw edema at 1, 2, 3 and 4 h intervals after carrageenan challenge. Pathological examinations and MPO activity also showed that both i.p. and i.c.v. maprotiline considerably inhibited infiltration of PMN leucocytes into the inflamed paws. Additionally, i.p. and i.c.v. maprotiline at all applied doses noticeably declined levels of IL-1β into the site of inflammation, while only i.p. maprotiline at a dose of 50 mg/kg significantly decreased TNF-α levels in the carrageenan-injected paws. These results confirmed anti-edematogenic activity of i.p. and i.c.v. maprotiline in the carrageenan induced paw edema model and showed that these properties of maprotiline might be mediated through inhibition of PMN infiltration and release of IL-1β and TNF-α.

Delphinidin inhibits IL-1β-induced activation of NF-κB by modulating the phosphorylation of IRAK-1(Ser376) in human articular chondrocytes

OBJECTIVE

In OA, there is enhanced expression of pro-inflammatory cytokines such as IL-1β in the affected joint. Delphinidin, an anthocyanidin found in pigmented fruits and vegetables, has been shown to possess anti-inflammatory and antioxidant properties. In the present study we determined whether delphinidin would inhibit the IL-1β-induced activation of NF-κB in human chondrocytes and determined the mechanism of its action.

METHODS

PGE2 levels and activation of NF-κB p65 in human OA chondrocytes were determined by ELISA-based assays. Protein expression of cyclo-oxygenase-2 (COX-2) and phosphorylation of kinases was determined by western immunoblotting. Expression level of mRNAs was determined by TaqMan assays.

RESULTS

Delphinidin inhibited IL-1β-induced expression of COX-2 and production of PGE2 in human chondrocytes. Delphinidin also inhibited IL-1β-mediated phosphorylation of IL-1 receptor-associated kinase-1(Ser376), phosphorylation of IKKα/β, expression of IKKβ, degradation of IκBα, and activation and nuclear translocation of NF-κB/p65. Phosphorylation of TGF-β-activated kinase 1 was not observed but NF-κB-inducing kinase (NIK) was phosphorylated and phosphorylation of NIK was blocked by delphinidin in IL-1β-treated human chondrocytes.

CONCLUSION

These data identify delphinidin as a novel inhibitor of IL-1β-induced production of cartilage-degrading molecule PGE2 via inhibition of COX-2 expression and provide new insight into the mechanism of its action. Our results also identify inhibition of IRAK1(Ser376) phosphorylation by delphinidin in IL-1β-induced activation of NF-κB in human chondrocytes. Given the important role played by IL-1β-induced NF-κB activation, COX-2 expression and PGE2 production in OA, our results may have important implications for the development of novel therapeutic strategies for the prevention/treatment of OA.

Pooled safety analysis of diclofenac sodium topical solution 1.5% (w/w) in the treatment of osteoarthritis in patients aged 75 years or older

Background

This study aimed to determine the safety of diclofenac sodium topical solution 1.5% (w/w) in 45.5% dimethyl sulfoxide (TDiclo) for the treatment of knee or hand osteoarthritis in persons aged 75 years or older.

Methods

A pooled analysis of safety data from seven multicenter, randomized, blinded, Phase III clinical trials (4–12 weeks’ duration) of TDiclo was conducted. The analysis focused on a subset of patients (n = 280) aged 75 years or older with a primary diagnosis of osteoarthritis of the knee (six trials) or hand (one trial). Patients received one of three topical treatments: TDiclo (n = 138); placebo (2.33% or 4.55% dimethyl sulfoxide, n = 39); or control (45.5% dimethyl sulfoxide, n = 103). Treatment groups were compared using Chi-square analysis, Fisher’s Exact test, or analysis of variance.

Results

The most common adverse events involved the skin or subcutaneous tissue, primarily at the application site. The incidence of dry skin was higher in the TDiclo (36.2%; P < 0.0001) and dimethyl sulfoxide control (18.4%; P = 0.0142) groups than in the placebo group (2.6%); the incidence of other skin or subcutaneous tissue adverse events was similar between the groups. Relatively few patients (<18%) experienced gastrointestinal adverse events, and group differences were not detected. In the TDiclo group, constipation (3.6%), diarrhea (3.6%), and nausea (3.6%) were the most common gastrointestinal adverse events. Cardiovascular and renal/ urinary adverse events were rare, and group differences were not detected. There was one case (0.7%) each of hypertension, spider veins, and vasodilation in the TDiclo group. Changes from baseline to the final visit in blood pressure and hepatic/renal enzyme levels were also similar between the groups.

Conclusion

TDiclo appears to be well tolerated for the treatment of osteoarthritis in persons aged 75 years or older.

Controlled release formulation of oxycodone in patients with moderate to severe chronic osteoarthritis: a critical review of the literature

Osteoarthritis (OA) is a physically and emotionally debilitating disease that predominantly affects the aging adult population. Current pharmacologic treatment options primarily consist of nonsteroidal anti-inflammatory drugs and/or acetaminophen, but associated side effects, analgesic limitations, especially in the elderly, and the need for around-the-clock analgesia have led physicians to search for alternative analgesics. Opioids have shown effectiveness at mitigating both chronic cancer and noncancer pain, and their ability to be placed into controlled release (CR) formulations suggests that they may prove efficacious for OA patients. One formulation, oxycodone CR, has shown effectiveness in cancer pain patients and in some trials of noncancer low back pain. In this review, the objective was to synthesize the reported findings by researchers in this field and present an up-to-date look at the efficacy, safety, and tolerability of oxycodone CR in OA patients. Public literature databases were searched using specific keywords (eg, oxycodone CR) for studies assessing the efficacy and safety profile of oxycodone CR and its use in patients with OA. A total of eleven articles that matched the criteria were identified, which included three placebo-controlled trials, six comparative trials, one pharmacokinetic study in the elderly, and one long-term safety trial. Analysis of the studies revealed that oxycodone CR is reasonably efficacious, safe, and tolerable when used to manage moderate to severe chronic OA pain, with similar side effects to that of other opioids.