Purpose

Wnt pathway upregulation contributes to osteoarthritis (OA) through increased osteoblast differentiation and increased catabolic enzyme/inflammatory cytokine levels. Lorecivivint (SM04690), a novel, small-molecule Wnt pathway inhibitor, previously demonstrated preclinical chondrogenesis and cartilage protection. Lorecivivint was evaluated in preclinical studies to determine its mechanism of action for Wnt pathway inhibition, chondrogenesis, and anti-inflammatory effects.

Methods and Materials

Kinase activity was measured using Z-LYTE and Lantha assays. Protein phosphorylation in human mesenchymal stem cells (hMSCs), chondrocytes, and synovial fibroblasts were measured by Western blot. Wnt pathway/chondrogenic genes and LPS-induced inflammatory cytokines were measured by qPCR in siRNA knockdowns (hMSCs/BEAS-2B cells). In vivo lorecivivint effects on inflammation, pain, and function were evaluated in rat OA models compared to vehicle.

Results

Lorecivivint inhibited intranuclear kinases cdc-like kinase 2 (CLK2, EC₅₀: 5.8 nM) and dual-specificity tyrosine kinase (DYRK1A, EC₅₀: 26.9 nM). Lorecivivint inhibited CLK2-mediated phosphorylation of serine and arginine rich splicing factor proteins and DYRK1A-mediated phosphorylation of Sirt1 and FoxO1. siRNA knockdowns identified roles for 1) CLK2 and DYRK1A in Wnt pathway modulation with no effects on β-catenin and 2) CLK2 inhibition in early chondrogenesis with DYRK1A inhibition playing a role in enhancing late chondrocyte function. NFKB/STAT3 inhibition by lorecivivint resulted in reduced inflammatory cytokine gene expression compared to controls. DYRK1A knockdown inhibited inflammation, and this effect was enhanced with combined DYRK1A/CLK2 knockdown. In vivo models showed that lorecivivint inhibited inflammatory cytokine production and expression of cartilage degradative enzymes, resulting in increased joint cartilage, decreased pain, and improved function.

Conclusion

Lorecivivint demonstrated a novel dual mechanism of action for Wnt pathway inhibition via CLK2 and DYRK1A, enhanced chondrogenesis and chondrocyte function, and reduced inflammation in rat models of knee OA (Figure). Lorecivivint may improve structure, symptoms, and function of knee OA.

Purpose

In a 52-week study, Wnt pathway inhibitor lorecivint (SM04690) showed subgroup improvements in knee osteoarthritis (KOA) pain, function, and joint space width compared to placebo (PBO). A 24-week study was conducted to refine patient-reported outcomes (PROs), target population, and dose. PROs from Weeks 12 and 24 are presented.

Methods and Materials

KOA subjects (KL grades 2-3, Pain Numeric Rating Scale [NRS] ≥4 and ≤8 in target knee and <4 in non-target knee) received 2 mL intra-articular lorecivivint (0.03, 0.07, 0.15, 0.23 mg) or PBO/sham injection. Endpoints included change from baseline to Week 24 in weekly average of daily Pain NRS [0-10], WOMAC Pain [0-100], WOMAC Function [0-100], and Patient Global Assessment (PtGA [0-100]) compared to PBO.

Results

695 subjects were dosed. Lorecivivint appeared well tolerated. Significant improvements from baseline compared to PBO were observed in Pain NRS for 0.07 mg and 0.23 mg groups at Weeks 12 and 24 (Figure). Similar improvements were observed in WOMAC Pain, WOMAC Function, and PtGA for 0.07 mg (Week 12) and 0.23 mg (Weeks 12 and 24) dose groups.

Conclusion

Lorecivivint, a potential disease-modifying KOA drug, demonstrated significant improvements in PROs compared to PBO up to 24 weeks for 0.07 mg and 0.23 mg dose groups.

Purpose

Treatment of osteoarthritis with novel injectable therapies could be improved by targetting the lesion sites in the articular cartilage. We have previously shown that degradation of Type II collagen in osteoarthritis occurs at the surface of the articular cartilage, leading to an accumulation of Type II collagen gelatin (1), a prime candidate for therapeutic targetting. Gelatinases A and B contain a catalytic domain as well as three fibronectin-like modules that form the collagen binding domain (CBD). The purpose of this study was to determine which of these modules is most important for binding to Type II collagen gelatin and to enhance the binding to this gelatin through mutations in its structure. The long-term goal is to deliver either drugs or cells (see Ref. 2) directly into the lesion sites.

Methods and Materials

Full length CBD, individual modules of CBD or mutations of these modules were expressed in E.coli shuffle cells, purified and then biotinylated before being tested for their ability to bind to denatured collagen types I and II by direct binding ELISA.

Results

CBD was found to have 10-fold higher binding (ie 10-fold lower Kd) to Type I collagen gelatin than Type II (Figure 1). Module 2 bound more tightly to gelatin than modules 1 or 3 (not shown), therefore we constructed a mutant CBD using three repeats of module 2 (222) and tested its binding . 222 had a 14-fold higher affinity for Type II collagen gelatin, with a Kd that was similar to that of is binding to Type I collagen gelatin (Figure 2).

Conclusion

The CBD mutant, protein 222, has a high binding capacity for Type II collagen gelatin and so could be used to target cells and drugs into cartilage lesions.

References

1. A. P. Hollanderet al., Journal of Clinical Investigation 96, 2859-2869 (1995)

2. J. P. Armstronget al., Nat Commun 6, 7405 (2015)

Purpose

FK506, an immunosuppressor, was reported to have the ability to suppress catabolic responses in primary human chondrocytes. However, immunosuppressive function of FK506 limited its use in cartilage osteoarthritis treatment. The purpose of this study was to evaluate the ability of FK506’s isomer, GPI-1046 in protecting against cartilage degeneration.

Methods and Materials

1ng/ml IL-1β was added to the medium of SW1353 to conduct osteoarthritis model. For treatment group, 0, 1, 10, 100, 200, and 500mM GPI-1046 were added to the medium. 10ug/ml FK506 was used as positive control. Cell viability was conducted. 24 and 48 hours later, QPCR and western blot were conducted to evaluate the protective effect of GPI-1046.

Results

Cell viability results showed that GPI-1046 had no obvious cytotoxicity. QPCR showed GPI-1046 up-regulated the expression of collagen type II and SOX 9, down-regulated the expression of MMP1, 3, 13. Western blot demonstrated that cartilage protection ability of GPI-1046 was even better than FK506.

Conclusion

GPI-1046 has the potential of protect against cartilage degeneration.

Purpose

Numerous treatment options have been proposed for affecting the natural history of knee osteoarthritis. Intra-articular injection with adipose-derived mesenchymal stem cells (MSCs) is an alternative to conventional methods. The aim of this study is to present 3-year mid-term results and the safety profile of this treatment option.

Methods and Materials

Twenty patients (10 women - 10 men, mean age 56.82±9.3 years and mean BMI 26.7±3.5) with knee mild and moderate osteoarthritis (Kellgren-Lawrence I-III) were treated with one intra-articular knee injection with autologous culture-expanded adipose-derived MSCs. The patients were evaluated before the injection and in 3rd, 6th, 12th, 24th, and 36th month after the treatment. Four subscales (Pain, Symptoms, Activity in Daily Living and Quality of Life) of Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire were used. Adverse effects and patients’ satisfaction was also recorded. The repeated measures ANOVA was used (p<0.05).

Results

No complications and/or adverse events had been reported. The ANOVA results indicated significant change over time for all KOOS subscales (p < 0.001). Post hoc testing confirmed significant changes in the Pain subscale between all-time points of measurements (p<0.001 to p=0.024) except for the 2nd year to 3rd year. Post hoc testing confirmed significant changes in the Symptoms subscale between all-time points of measurements (p<0.001 to p=0.046) except for the 2nd year to 3rd year. The ADL subscale changed significantly in each time period after injection (p<0.001 to p=0.019). The ADL subscale did not change significantly between 6 months and 1 year but significant changes were found between 6 months and 2, 3 years (p<0.001). Post hoc testing confirmed significant changes in the QoL subscale between all-time points of measurements (p<0.001 to p=0.001).

Conclusion

Knee intra-articular injection of adipose-derived MSCs is a safe conservative treatment option for degenerative knee osteoarthritis, with promising mid-term results concerning the knee joint function and pain reduce.

Purpose

Although the association between bone mineral density (BMD) and osteoarthritis (OA) has been reported, the relationship of BMD and OA has long been still controversial. The aim of this study was to evaluate the association between knee OA and BMD of body parts in relation to sex.

Methods and Materials

This study was designed as a cross sectional analysis using data on BMDs of body parts measured using dual energy X-ray absorptiometry in 7764 people in the Fourth and Fifth Korea National Health and Nutrition Examination Survey. Knee OA was assessed from a weight-bearing anteroposterior radiography and graded on a scale of Kellgren-Lawrence (KL) grade. The radiographic OA was defined as the participants who had a KL grade≥2. The associations between knee OA and BMD of body parts (Total, pelvis and lower leg) were assessed. The BMDs of the body part was divided into quartiles and the relationship between OA and BMD was examined according to sex.

Results

The Total, pelvis and lower leg BMDs were negatively related with the increase of KL grade in women (all p<0.001). However, none of body parts BMDs showed significant association from KL grade 0 to 4 in men (all p>0.05). There was a significant correlation with decreasing linear trend between the odds ratios of each quarter percentile group of total, pelvis and lower leg BMDs, and knee OA in women (all p <0.05). After adjusting for age, waist circumference, the presence of hypertension and diabetes, smoking, alcohol, the significant association has been maintained (all p<0.05). However, there were no relationships between all BMD of each body parts and knee OA before and after adjusting for aforementioned variables in men (all p>0.05).

Conclusion

Low BMDs of body parts including total, pelvis and lower leg were associated with the presence and degree of knee OA in women, but not in men.

Purpose

REG-O3 is an innovative chimeric peptide combining a short amino acid sequence derived from growth hormone and an analog of somatostatin, both molecules involved in cartilage repair and anti-inflammatory processes, respectively. This peptide was therefore thought to show disease modifying osteoarthritis drug (DMOAD) potential and protect articular structure from osteoarthritis. This study aimed to investigate the DMOAD potential of REG-O3 by analyzing its effect on pain, joint function and structure, upon injection into osteoarthritic rat knee joint.

Methods and Materials

Osteoarthritis was induced in the right knee of mature male Lewis rats (n=12/group) by the surgical transection of the anterior cruciate ligament (ACLT) combined with the partial medial meniscectomy (pMMx). Treatments were administered intra-articularly (50µL) into the right operated knee from 14 days after surgery through 3 consecutive injections one week apart. REG-O3, solubilized in a liposomal solution, was injected into the right operated knee at either 5, 25 or 50 µg and compared to placebo (liposomal solution), and positive control items (dexamethasone [0.5 mg/kg], hyaluronic acid [HA, 1 mg/kg]). The study endpoints were the pain and function measured throughout the entire study once a week and the structure of the knee joint evaluated 8 weeks after surgery using OARSI score.

Results

ACLT/pMMx surgery induced a significant decrease of right operated paw weight bearing in all groups. Compared to liposomal solution, REG-O3 was able to significantly improve weight bearing both as efficiently as dexamethasone and more potently than HA. When looking at cartilage histology, REG-O3 (25µg) was the only treatment able to significantly improve cartilage OARSI global score and to significantly reduce total cartilage degeneration width, cartilage matrix loss width and cartilage degeneration.

Conclusion

This study provides evidence of a remarkable protecting effect of REG-O3 on pain/joint function and cartilage/matrix degeneration in ACLT/pMMx model of rat osteoarthritis. REG-O3 displays an interesting profile as a DMOAD.

Purpose

There is no cure or disease modifying drugs available to treat osteoarthritis (OA). Therefore, effective biomarkers and diagnostic tests are direly needed to monitor the disease progression and treatment. The objective of this study is to identify and evaluate mediators that serve as biomarkers of OA progression and treatment.

Methods and Materials

The rehabilitation protocol for patients with mild to moderate knee OA consisted of muscle strengthening exercises activating: hamstrings, quadriceps, and gluteal muscles, during 8 weeks (3 session/week). The efficacy of protocol was evaluated by functional scale (WOMAC), quality of life questionnaire (EuroQol), pain scale (VAS), and physical function tests (TUG, isokinetic dynamometer). Serum levels of COMP (cartilage oligomeric matrix protein), CS846 (aggrecan neoepitope), C2C (cleavage of type II collagen), IL-6,-8 and-10, and, HMGB1 (High mobility group box 1) were evaluated by ELISA. All outcomes were performed before and after the rehabilitation program. A correlation of physical improvement and serum biomarkers was performed. Statistical analyzes were performed by Student's t-Test, one/two-way ANOVA and Pearson's Correlation.

Results

Thirty six individuals (23 women and 13 man) with moderate knee OA (KL 2-3; age: 55.1 ± 5.29 years; BMI: 28.9 ± 3.8 Kg/m2; Mean ± SD), were evaluated. After the treatment, the subjects reached 50% reduction in the WOMAC scale, significantly showing an improvement in pain, stiffness, mobility, and functional test performance. And also an increased maximal strength production and maximal strength lift capacity for the knee extensor and flexor muscles and improved muscle balance. There was no significant difference in levels of serum biomarkers after the treatment and no evidence of correlation between biomarkers serum levels and clinical improvement.

Conclusion

Physical exercise resistance was sufficient to reduce pain, increase strength production, improve functional performance and muscle balance of OA subjects. However, biomarkers do not present evidence to monitor clinical improvement after conservative treatment.

Purpose

Biomarkers in early osteoarthritis (eOA) could serve as surrogate endpoints for clinical trials and allow early clinical intervention to slow progression of the disease. The aims of this review were to provide a comprehensive list of molecular biomarkers and biomarker panels to aid in the diagnosis of early knee osteoarthritis (eOA) that have been reported since August 2013.

Methods and Materials

MEDLINE and Embase databases were searched from August 2013 to May 2018 using the keywords “knee osteoarthritis”, “hip osteoarthritis”, “osteoarthritis” and “biomarker”. Studies were screened by abstract initially using the inclusion and exclusion criteria.

Results

A total of 95 statistically significant, individual, molecular biomarkers were identified. Indian hedgehog protein, interleukin-8 and Chemokine (C-C motif) ligand 3 (CCL3) all had the ability to discern eOA patients from both healthy controls and individuals with advanced osteoarthritis. CCL3 had an area under the receiver operating characteristic curve (AUC) of 0.799 when diagnosing eOA. 11 biomarker panels were identified across 6 studies. One panel combined anti-cyclic citrullinated protein antibody with biomarkers of protein oxidation, nitration and glycation and had an AUC=0.98 when diagnosing eOA. Another panel achieved an AUC=0.872 when predicting the incidence of OA over 2.5 years in healthy controls. Biomarker panels did not perform as well at predicting 24-month case status in individuals already diagnosed with OA.

Conclusion

CCL3 was the most capable singular biomarker for diagnosing eOA. However, biomarker panels performed the best when diagnosing eOA. In order for further research to be as effective as possible a universal consensus must be reached regarding the definition and staging of eOA. The biomarkers and biomarker panels identified from this review have the ability to provide an objective method to aid clinicians and researchers in diagnosing osteoarthritis in its early stages.

Purpose

To correlate the metabolomic profile of synovial fluid from patients with and without knee OA and clinical factors predisposing to OA development.

Methods and Materials

Synovial fluid (SF) had been collected from patients submitted to knee arthroscopy (n=11; K-L 0/1) or knee replacement (n=37, 9 K-L 3 and 26 K-L 3/4), centrifuged to isolate cells from the fluid, and then submitted to metabolomics analysis through NMR spectra acquired on Bruker 400MHZ spectrometer. ¹H one-dimensional spectra were acquired with ZGESGP, 1K scans, TD of 64K, and SW of 20ppm. Two-dimensional ¹H-¹HTOCSY was acquired for assignments. Inversion-recovery-T1 was acquired to each sample to observe viscosity. All spectra were processed, phase and baseline corrected, on TopSpin 3.2 software (Bruker). CCPNMR V2 software, with metabolomics package installed¹, HMDB 3.0², and BMRB³, were used to assignments. For multivariate analysis, 1D spectra were aligned, normalized by sum of intensities, 0.02ppm binned and pareto scaled, on AMIX software (Bruker). PLS-DA, VIP-score, and cross-validation, were done on MetaboAnalyst 3.0⁴. For univariate analysis, we did multiple t-test, with 95% CI, and same SD between control/disease samples, on GraphPad Prism 6 software. Using records from a database of a previous study and medical records form the patients included, we performed a multivariate analysis of the data obtained. Clinical data as glucose levels, body mass index and OA severity were obtained from medical and radiological records.

Results

We found that among the variables studied, only OA severity levels were able to distinguish between different classes of patients according to the metabolomic profile. We found no differences regarding glucose levels and body mass index.

Conclusion

Our preliminary data suggests that although metabolic syndrome and OA are close related, glucose levels and BMI were not able to distinguish metabolomics profiles of OA patients.