Biomarkers for Femoroacetabular Impingement and Hip Osteoarthritis: A Systematic Review and Meta-analysis

Elevated secretion of pro-collagen I-alpha and vascular endothelial growth factor as biomarkers of acetabular labrum degeneration and calcification in hip osteoarthritis: An explant study

Background

Hip osteoarthritis (OA) involves structural degeneration of different joint compartments, including femoral head cartilage, periarticular ligaments and the acetabular labrum. However, the molecular mechanisms underlying labrum degeneration in hip OA remain poorly understood.

Aim

To assess secretion of putative biomarkers for OA from explanted human labrum tissues under basal and inflammatory conditions and to determine whether these could differentiate between OA and calcification status compared to fracture controls.

Methods

Intact labrum specimens were collected from patients undergoing joint arthroplasty for primary hip OA (n ​= ​15, mean age 70) or non-OA femoral neck fracture (n ​= ​5, mean age 64). Tissues were dissected in equal-sized samples and explanted for one week. To mimic activation of inflammatory signaling by endogenous damage-associated molecular patterns (DAMP) tissue were stimulated with a toll-like receptor 4 (TLR4) agonist (1 ​μg/mL LPS). The involvement of transforming growth factor-beta (TGF-beta) signaling was evaluated by treatment with a TGF-beta type 1 receptor inhibitor (10 ​μM SB-505124). Secretion of aggrecan (ACAN), pro-collagen-I alpha (Pro-Col-Iα), cartilage oligomeric matrix protein (COMP), interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) was assessed by enzyme-linked immunosorbent assay (ELISA). Labrum calcification was evaluated by 3D whole mount fluorescent microscopy of ethyl cinnamate-based optically cleared tissues stained with Alcian blue/Alizarin red.

Results

Whole mount microscopy revealed non-OA fracture controls were non-calcified, whereas six OA labra (40%) were partially calcified or ossified. Basal secretion of Pro-Col-Iα and VEGF was increased four-fold in OA versus non-OA labra. Pro-Col-Iα levels were correlated with those of VEGF (r ​= ​0.65) and COMP (r ​= ​0.54). Stimulation of DAMP signaling through TLR4 affected secretion of IL-6, VEGF, COMP and Pro-Col-Iα, with distinct responses between non-OA and OA tissues. Inhibition of TGF-beta signaling specifically reduced elevated secretion of Pro-Col- Iα and VEGF in calcified OA labrum.

Conclusions

Secretion of the putative OA biomarkers Pro-Col-Iα and VEGF is elevated in degenerated human acetabular labrum and may serve as indicators of OA and calcification status. Secretion of both factors was partially regulated by TGF-beta signaling in calcified OA labrum tissues.The Translational potential of this article:Our findings suggest that a biomarker panel consisting of Pro-Col-Iα/VEGF/COMP may be valuable for assessing subradiographic labrum degeneration and calcification in hip OA. Targeting TGF-beta signaling may offer a means to reduce vascular invasion and fibrosis in acetabular labrum tissue.

Clinical use of autologous adipose-derived stromal vascular fraction cell injections for hip osteoarthritis

Introduction

Currently, studies on adipose-derived stromal vascular fraction (SVF) cells are attracting increasing attention because they have the potential to differentiate into a subset of cell types, such as bone marrow-derived mesenchymal stromal cells (MSCs), and are easier to harvest than MSCs, thus making them easier to apply clinically. This study evaluated the short-term clinical outcomes of SVF cell therapy for hip osteoarthritis (OA).

Methods

Forty-two patients were enrolled in this study; these patients received a single injection comprising an average of 3.8 (standard deviation [SD], ±1.3) × 10⁷ SVF cells into the hip joint. All patients were followed-up for at least 6 months. The mean age of the patients was 60.2 years (SD, ±9.4 years). Kellgren-Lawrence (KL) grades II, III, and IV based on radiography were 13, 13, and 16 patients, respectively. SVF cells were obtained from the subcutaneous fat of the abdomen or breech using a Celution® 800/CRS system. The average cell viability of SVF cells was 90.8% (SD, ±2.8%). Clinical assessments were performed using the Harris Hip Score (HHS), Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) score, and visual analog scale (VAS) score to evaluate pain. Images were evaluated using radiography, and T2 mapping values were obtained using a 1.5-T magnetic resonance imaging system. These clinical and imaging assessments were followed from preoperatively to 6 months postoperatively.

Results

The HHS, JHEQ score, and VAS score improved significantly from 22.5 (SD, ±16.6), 26.6 (SD, ±11.3), and 75.5 (SD, ±15.8) preoperatively to 46.8 (SD, ±27.2), 39.4 (SD, ±19.7), and 46.5 (SD, ±27.9), respectively, at 6 months postoperatively. KL grade II showed significant improvement in clinical outcome from preoperative to postoperative, while KL grade IV showed slight or little improvement. The center edge angle, acetabular head index on the radiographs, and T2 mapping values did not change significantly from preoperatively to 6 months postoperatively.

Conclusions

SVF cell injection in the hip joint showed good short-term clinical efficacy for reducing hip OA symptoms. SVF cell therapy is thus an innovative and effective treatment for hip OA.

A quasi-experimental study of group counselling effectiveness for patient functional ability and quality of counselling among patients with hip arthroplasty

AIM

The aim of this study was to investigate effectiveness of group counselling for the patients with hip arthroplasty, self-assessed functional ability, and quality of counselling.

DESIGN

A quasi-experimental study.

METHOD

The questionnaire included the Counselling Quality Instrument (CQI), Harris hip score and Oldwellactive self-rated wellness profile. A Mann-Whitney U- and chi-squared and t-tests were used. A Wilcoxon singed rank test were used to evaluate changes in functional ability.

NO PATIENT OR PUBLIC CONTRIBUTION

Patients and the public were not involved in the design, recruitment and implementation of this study.

RESULTS

Fifty patients participated. Patients reported better results for limping (p = 0.000), walking distance (p = 0.000) and use of a walking aid (p = 0.001) in the follow-up time point and they pain decreased. Patients were satisfied with interactions during counselling; gender (p = 0.000) and use of a walking aid (p = 0.044) were found to significantly affect. A lack of goal-oriented counselling was in depressive symptoms (p = 0.016), worries (p = 0.010) and loneliness (p = 0.026).

In major joint diseases the human synovium retains its potential to form repair cartilage

The inner surface layer of human joints, the synovium, is a source of stem cells for the repair of articular cartilage defects. We investigated the potential of the normal human synovium to form novel cartilage and compared its chondrogenic capacity with that of two patient groups suffering from major joint diseases: young adults with femoro-acetabular impingement syndromes of the hip (FAI), and elderly individuals with osteoarthritic degeneration of the knee (OA). Synovial membrane explants of these three patient groups were induced in vitro to undergo chondrogenesis by growth factors: bone morphogenetic protein-2 (BMP-2) alone, transforming growth factor-β1 (TGF-β1) alone, or a combination of these two. Quantitative evaluations of the newly formed cartilages were performed respecting their gene activities, as well as the histochemical, immunhistochemical, morphological and histomorphometrical characteristics. Formation of adult articular-like cartilage was induced by the BMP-2/TGF-β1 combination within all three groups, and was confirmed by adequate gene-expression levels of the anabolic chondrogenic markers; the levels of the catabolic markers remained low. Our data reveal that the chondrogenic potential of the normal human synovium remains uncompromised, both in FAI and OA. The potential of synovium-based clinical repair of joint cartilage may thus not be impaired by age-related joint pathologies.

Hip Osteoarthritis and the Risk of Lacunar Stroke: A Two-Sample Mendelian Randomization Study

Whether hip osteoarthritis (OA) could increase the risk of lacunar stroke (LS) is not well understood. This two-sample Mendelian randomization (MR) study aimed to investigate in depth the effect of genetically predicted hip OA on LS risk. Hip OA-related instrumental variables (IVs) were selected from a genome-wide association study (GWAS) of 393,873 individuals. The summary data of LS were obtained from a GWAS meta-analysis, including 16,030 cases and 248,929 controls. We used the inverse-variance weighted (IVW) as the primary MR analysis method. Moreover, the weighted-median, MR-Egger regression, and the MR pleiotropy residual sum and outlier (MR-PRESSO) test were supplementary methods. The sensitivity analysis was performed using the leave-one-out test. We identified the positive causal relationship between hip OA and the risk of LS (odds ratio [OR] = 1.20, 95% confidence interval [CI]: 1.07, 1.36; p = 0.002 using the IVW method). The weighted median method provided similar results. There was no evidence of directed pleiotropy, and sensitivity analysis results were stable, suggesting the robustness of our study. This study showed a causal effect of hip OA on the risk of LS, and more efforts should be made to explore the potential mechanisms in the future.

Inhibition of nuclear receptor RORα attenuates cartilage damage in osteoarthritis by modulating IL-6/STAT3 pathway

Osteoarthritis (OA) is characterized by cartilage destruction, chronic inflammation, and local pain. Evidence showed that retinoic acid receptor-related orphan receptor-α (RORα) is crucial in cartilage development and OA pathogenesis. Here, we investigated the role and molecular mechanism of RORα, an important member of the nuclear receptor family, in regulating the development of OA pathologic features. Investigation into clinical cartilage specimens showed that RORα expression level is positively correlated with the severity of OA and cartilage damage. In an in vivo OA model induced by anterior crucial ligament transaction, intra-articular injection of si-Rora adenovirus reversed the cartilage damage. The expression of cartilage matrix components type II collagen and aggrecan were elevated upon RORα blockade. RNA-seq data suggested that the IL-6/STAT3 pathway is significantly downregulated, manifesting the reduced expression level of both IL-6 and phosphorylated STAT3. RORα exerted its effect on IL-6/STAT3 signaling in two different ways, including interaction with STAT3 and IL-6 promoter. Taken together, our findings indicated the pivotal role of the RORα/IL-6/STAT3 axis in OA progression and confirmed that RORα blockade improved the matrix catabolism in OA chondrocytes. These results may provide a potential treatment target in OA therapy.

Targeted treatment for osteoarthritis: drugs and delivery system

The management of osteoarthritis (OA) is a clinical challenge due to the particular avascular, dense, and occluded tissue structure. Despite numerous clinical reports and animal studies, the pathogenesis and progression of OA are still not fully understood. On the basis of traditional drugs, a large number of new drugs have been continuously developed. Intra-articular (IA) administration for OA hastens the development of targeted drug delivery systems (DDS). OA drugs modification and the synthesis of bioadaptive carriers contribute to a qualitative leap in the efficacy of IA treatment. Nanoparticles (NPs) are demonstrated credible improvement of drug penetration and retention in OA. Targeted nanomaterial delivery systems show the prominent biocompatibility and drug loading-release ability. This article reviews different drugs and nanomaterial delivery systems for IA treatment of OA, in an attempt to resolve the inconsonance between in vitro and in vivo release, and explore more interactions between drugs and nanocarriers, so as to open up new horizons for the treatment of OA.

Mesenchymal Stem Cells injection in hip osteoarthritis: preliminary results

Background and aim of the work: Osteoarthritis will become even more common in the near future since the average life span is steadily growing. Pain and loss of function are the main complaints reported by patients, inevitably leading towards a worsened daily life performance. New modern techniques have been developed with advanced cell based therapies. Mesenchymal stem cells (MSC) have the inner ability to mature into different types of cells depending on the stimuli they undergo. This technique has already been proven successful in the knee and, with this retrospective study, we would like to assess its feasibility in the hip joint. Methods:6 consecutive patients affected by hip osteoarthritis were treated by intra-articular injection of autologous adipose-derived MSC between June 2017 and June 2018. Our study included only patients with constant hip pain resistant conservative treatment and OA graded 0-2 on the Tonnis grading scale. All 6 patients were evaluated in the preoperative setting and at the 6 months post-operative mark. Results: The HHS showed an improvement from the pre-operative baseline mean value of 67.2±3.4 to the 84.6±6.3 post-operative value. Moreover, the WOMAC score dropped from a baseline score of 36.3±4.7 to 19.8±3.4 at 6 months’ post-op follow up visit. Conclusions: MSC Lipogems is a fairly easy technique. No adverse effects were recorded in our experience. Preliminary results showed a positive outcome according to all the grading systems used in this study even though a longer follow up is needed to validate this technique. (www.actabiomedica.it)