Hemoglobin stimulates the expression of matrix metalloproteinases, MMP-2 and MMP-9 by synovial cells: a possible cause of joint damage after intra-articular hemorrhage

Synovitis and joint health in patients with haemophilia: Statements from a European e-Delphi consensus study

INTRODUCTION

Synovitis, a common feature in haemophilia, is triggered by the presence of blood in joints, and represents the first step towards the development of chronic arthropathy. Synovitis may be detected early by means of ultrasound or magnetic resonance imaging scan; clinical joint scores are less sensitive in this setting. Regular long-term prophylaxis with clotting factor concentrates, as primary prophylaxis and tailored to individual needs, has high efficacy in preventing synovitis. In general, higher factor levels lower bleeding risk, but no direct correlation between factor levels and synovitis incidence has been demonstrated.

AIM

This study aimed to develop an expert consensus relating to the definition, pathophysiology, diagnosis, prevention, follow-up and treatment of synovitis, recognising its relevance for joint health and taking into account existing knowledge gaps.

METHODS

A Delphi consensus study was designed and performed. An expert group prepared 22 statements based on existing literature; a wider expert panel subsequently voted on these.

RESULTS

Retention of panellists was high. Four statements required amending and consensus on all statements was achieved after three rounds of voting.

CONCLUSION

This e-Delphi consensus study addressed the importance of synovitis in joint health of people with haemophilia and highlighted knowledge gaps in this field. Studies on the natural course of synovitis are lacking and the biological mechanisms underlying this process are not yet fully elucidated. While basic and clinical research proceeds in this field, expert consensus can help guide clinicians in their routine clinical practice, and Delphi methodology is often used to produce best-practice guidelines.

Extracellular Hemoglobin: Modulation of Cellular Functions and Pathophysiological Effects

Hemoglobin is essential for maintaining cellular bioenergetic homeostasis through its ability to bind and transport oxygen to the tissues. Besides its ability to transport oxygen, hemoglobin within erythrocytes plays an important role in cellular signaling and modulation of the inflammatory response either directly by binding gas molecules (NO, CO, and CO2) or indirectly by acting as their source. Once hemoglobin reaches the extracellular environment, it acquires several secondary functions affecting surrounding cells and tissues. By modulating the cell functions, this macromolecule becomes involved in the etiology and pathophysiology of various diseases. The up-to-date results disclose the impact of extracellular hemoglobin on (i) redox status, (ii) inflammatory state of cells, (iii) proliferation and chemotaxis, (iv) mitochondrial dynamic, (v) chemoresistance and (vi) differentiation. This review pays special attention to applied biomedical research and the use of non-vertebrate and vertebrate extracellular hemoglobin as a promising candidate for hemoglobin-based oxygen carriers, as well as cell culture medium additive. Although recent experimental settings have some limitations, they provide additional insight into the modulatory activity of extracellular hemoglobin in various cellular microenvironments, such as stem or tumor cells niches.

Autologes plättchenreiches Plasma in der Behandlung der Alopezie

Autologes plättchenreiches Plasma wird aufgrund seiner wundheilenden Eigenschaften vielfach angewandt u. a. in Orthopädie, Chirurgie und Dermatologie. Zunehmend stellt plättchenreiches Plasma außerdem bei bestimmten Formen der Alopezie eine interessante neue Behandlungsoption dar, sei es als alleinige Therapie oder auch als Adjuvans im Rahmen einer Haartransplantation. Kontrollierte klinische Studien an kleineren Patientengruppen zeigten vielfach positive Ergebnisse, größere Studien stehen bislang noch aus. Die Wirkung auf das Haarwachstum wird sehr wahrscheinlich über die in plättchenreichem Plasma enthaltenen Wachstumsfaktoren und Zytokine vermittelt.

Blood in the joint: effects of hemarthrosis on meniscus health and repair techniques

Injury to the meniscus is common and frequently leads to the development of post-traumatic osteoarthritis (PTOA). Many times meniscus injuries occur coincident with anterior cruciate ligament (ACL) injuries and lead to a bloody joint effusion. Hemarthrosis, or bleeding into the joint, has been implicated in degeneration of joint tissues. The goal of this review paper is to understand the pathophysiology of blood-induced joint damage, the possible effects of blood on meniscus tissue, and the implications for current meniscus repair techniques that involve the introduction of blood-derived products into the joint. In this review, we illustrate the similarities in the pathophysiology of joint damage due to hemophilic arthropathy (HA) and osteoarthritis (OA). Although numerous studies have revealed the harmful effects of blood on cartilage and synovium, there is currently a gap in knowledge regarding the effects of hemarthrosis on meniscus tissue homeostasis, healing, and the development of PTOA following meniscus injury. Given that many meniscus repair techniques utilize blood-derived and marrow-derived products, it is essential to understand the effects of these factors on meniscus tissue and the whole joint organ to develop improved strategies to promote meniscus tissue repair and prevent PTOA development.

Hemoglobin stimulates the expression of ADAMTS-5 and ADAMTS-9 by synovial cells: a possible cause of articular cartilage damage after intra-articular hemorrhage

Background

ADAMTS (a disintegrin and metalloprotease with thrombospondin motifs) proteins play an important pathological role in matrix degeneration. Aggrecan degradation is a significant and critical event in early-stage osteoarthritis. To determine the effect of hemoglobin (Hb) on the ability of synovial tissues to produce ADAMTS family members, we examined the influence of Hb by synovial cells in an in vitro experimental system.

Methods

Synovial tissues were obtained from five young patients with meniscal injury under arthroscopic surgery. Primary cultures of human knee synovial cells were treated with different doses of human Hb (0, 25, 50, 100 μg/ml). The culture media were collected 24 h after Hb-treatment. In the time-course studies, cells were treated with and without 100 μg/ml Hb, and culture media were taken at 6, 12, and 24 h. To identify the proteins responsible for aggrecanase activity, Western blot analysis using antibodies against human ADAMTS-5, −8, −9, and −10; enzyme-linked immunosorbent assay (ELISA); and gene expression for ADAMTS-5 and -9 were examined. Statistical comparisons between each group were performed using paired t-tests.

Results

Western blot analysis revealed that Hb-treatment resulted in the expression of ADAMTS-5 and -9. Neither control group nor Hb-treated medium showed immunoreactivity against ADAMTS-8 or −10. In a dose-dependency study, the Hb-treated group showed significantly higher levels of ADAMTS-5 and -9 compared with the control (p < 0.05). There was no significant difference between 25, 50, and 100 μg/ml Hb-treated groups. In a time-course study, the ADAMTS-5 and -9 levels in the conditioned medium had significantly increased expression at 6, 12, and 24 h in the Hb-treated group (p < 0.05). Hb evoked significant expression of ADAMTS-9 mRNA at 12 and 24 h (p < 0.05).

Conclusions

These findings indicate that Hb induces the expression of ADAMTS-5 and -9 by synovial cells at low doses, even at an acute phase, and suggests a possible role for Hb in cartilage damage after intra-articular hemorrhage. The results also suggest a new potential therapeutic target by inhibiting the activities of ADAMTS-5 and -9 to prevent cartilage damage after intra-articular hemorrhage.

TAK1 inhibition attenuates both inflammation and fibrosis in experimental pneumoconiosis

Pneumoconiosis, caused by inhalation of mineral dusts, is a major occupational disease worldwide. Currently, there are no effective drugs owing to a lack of potential therapeutic targets during either the inflammation or fibrosis molecular events in pneumoconiosis. Here, we performed microarrays to identify aberrantly expressed genes in the above molecular events in vitro and found a hub gene transforming growth factor-β-activated kinase 1 (TAK1), which was highly expressed and activated in pneumoconiosis patients as well as silica-exposed rats with experimental pneumoconiosis. Genetic modulation of TAK1 by CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9, RNA interference and overexpression indicated the important role of TAK1 in both inflammation and fibrosis in experimental pneumoconiosis. To achieve pharmacological TAK1 inhibition, we virtually screened out a natural product resveratrol, which targeted TAK1 at both N161 and A107 residues, and significantly inhibited TAK1 activation to attenuate inflammation and fibrosis in vitro. Consistently, in vivo prevention and intervention studies showed that resveratrol could inhibit pulmonary inflammation and fibrosis in silica-exposed rats.

Black Colouration of the Knee Articular Cartilage after Spontaneously Recurrent Haemarthrosis

Mild discolouration of the articular cartilage is known to gradually occur during aging. However, pathological tissue pigmentation is occasionally induced under several specific conditions. In the present case, we performed total knee replacement in a patient with recurrent haemarthrosis. However, during the operation, we observed severe black colouration of the knee articular cartilage, due to the deposition of hemosiderin and lipofuscin. To our knowledge, this is the first report of severe cartilage pigmentation, due to hemosiderin and lipofuscin deposition in articular cartilage.

Do gene expression changes in articular cartilage proteases of the synovial membrane correlate with expression changes of the same genes in systemic blood cells?

PURPOSE

The aim of our study was to find whether an injury of the knee joint tissues increases gene expression of selected hyaline cartilage degenerating enzymes such as matrix metaloproteinases (MMP) and aggreacaneses (Agg).

METHODS

A total of 138 patients (81 female, 57 male) were admitted for knee arthroscopy with a mean age of 38.8 years. Full blood samples were collected preoperatively and synovium samples intraoperatively. Joint tissue lesions such as menisci, anterior cruciate ligament (ACL) and hyaline cartilage were estimated. Real time PCR with spectrophotometric analysis was performed.

RESULTS

An ACL lesion was found in 56 patients, medial menisci (MM) in 65, and lateral menisci (LM) in five. Chondral lesions were estimated according to Outerbridge's grading system. In laboratory tests correlation between ACL tear and gene expression was seen except TIMP1 in serum (p < 0.05). In MM lesions MMP9, Agg2 elevation in serum was observed. LM lesions erased MMP13, MMP14 in serum and MMP8 in synovium. Chondral lesions revealed that many genes had higher expression in patients without hyaline degeneration. All of the gene expressions correlated between serum and synovium.

CONCLUSION

An ACL lesion provokes elevation in expression of proteases genes, while the influence of other lesions remains elusive. Gene expression in synovium correlates with peripheral blood.

An experimental study to compare inflammatory response due to liquid or gas joint distension in horses submitted to arthroscopy

PURPOSE

To assess comparatively the inflammatory response that follows CO(2) or Ringer's lactate joint capsular distension of horses submitted to experimental arthroscopy

METHODS

Each animal was submitted to a bilateral tarsocrural arthroscopy employing gas distention in one joint and fluid distention in the contralateral joint. Synovial fluid was evaluated at 0, six, 12, 24 and 48 hours post-operative.

RESULTS

The use of CO(2) for arthroscopy causes an acute and mild synovitis alike to the liquid capsular distension, showing similar synovial fluid increase of leukocytes, TP, and TNF-α. Although synovial fluid PGE(2) content was higher in joints submitted to CO(2) distension, lower levels of hemoglobin and leukocytes oxidative burst after surgery indicates that CO(2) arthroscopy decreased intra-articular bleeding and activation of infiltrating leukocytes.

CONCLUSIONS

The use of CO(2) for arthroscopic examination causes acute and mild synovitis that is similar to the effects caused by the liquid capsular distension. CO2 also seems to decrease intra-articular bleeding and activation of leukocytes.

Hemorrhagic activity of HF3, a snake venom metalloproteinase: insights from the proteomic analysis of mouse skin and blood plasma

Hemorrhage induced by snake venom metalloproteinases (SVMPs) is a complex phenomenon resulting in capillary disruption and blood extravasation. The mechanism of action of SVMPs has been investigated using various methodologies however the precise molecular events associated with microvessel disruption remains not fully understood. To gain insight into the hemorrhagic process, we analyzed the global effects of HF3, an extremely hemorrhagic SVMP from Bothrops jararaca, in the mouse skin and plasma. We report that in the HF3-treated skin there was evidence of degradation of extracellular matrix (collagens and proteoglycans), cytosolic, cytoskeleton, and plasma proteins. Furthermore, the data suggest that direct and indirect effects promoted by HF3 contributed to tissue injury as the activation of collagenases was detected in the HF3-treated skin. In the plasma analysis after depletion of the 20 most abundant proteins, fibronectin appeared as degraded by HF3. In contrast, some plasma proteinase inhibitors showed higher abundance compared to control skin and plasma. This is the first study to assess the complex in vivo effects of HF3 using high-throughput proteomic approaches, and the results underscore a scenario characterized by the interplay between the hydrolysis of intracellular, extracellular, and plasma proteins and the increase of plasma inhibitors in the hemorrhagic process.

Blood exposure has a negative effect on engineered cartilage

PURPOSE

The aim of this study was to investigate the in vitro effect of different concentrations of blood on the morphological and biochemical properties of engineered cartilage. Previous studies have demonstrated a negative effect of blood on native cartilage; however, the effect of the contact of blood on engineered cartilage is unclear.

METHODS

Articular chondrocytes were isolated from swine joints, expanded in monolayer culture, and seeded onto collagen membranes. The seeded membranes were cultured for 3 days in the presence of different concentrations of peripheral blood. Some samples were retrieved at the end of the blood contact, others after 21 additional days of standard culture conditions, in order to investigate the "long-term effect" of the blood contact.

RESULTS

All seeded samples showed an increase in the weight and an evident cartilage-like matrix production. A concentration-dependent reduction in the mitochondrial activity due to blood contact was shown at the earlier culture time, followed by a partial recover at the longer culture time.

CONCLUSION

A blood contact of 3 days affected the chondrocytes' activity and determined a delay in the maturation of the engineered cartilage. These findings have clinical relevance, as autologous chondrocytes seeded onto biological scaffolds has become an established surgical method for articular cartilage repair. Therefore, further investigation into material sciences should be encouraged for the development of scaffold protecting the reparative cells from the blood insult.

Peripheral blood level alterations of MMP-2 and MMP-9 in patients with chronic kidney disease on conservative treatment and on hemodialysis

OBJECTIVES

Data concerning the levels of metalloproteinase-2 (MMP-2) and MMP-9 in uremia and dialysis are conflicting and incomplete.

DESIGN AND METHODS

We measured the serum MMP levels in patients with chronic kidney disease (CKD) and undergoing maintenance hemodialysis (HD), and we tried to identify factors that could affect their levels.

RESULTS

MMP-2 and the high sensitivity C-reactive protein (hsCRP) were inversely correlated with hematological parameters in the whole CKD group. CKD patients with stages 3+4 showed a significant increase in the MMP-9 levels compared to the other studied groups; this metalloproteinase was inversely correlated with lymphocyte count, and positively correlated with the hsCRP. The MMP-2 levels were higher in pre and post HD patients compared to the control group and CKD stage 1+2. In contrast, there was no difference in the MMP-9 levels. Both MMP-2 and MMP-9 were associated with the leukocyte count in pre HD group.

CONCLUSIONS

This study suggests a connection between an inflammatory state, biochemical response and the MMP levels in uremic and dialysis patients.

Biotribological and biomechanical changes after experimental haemarthrosis in the rabbit knee

Changes in articular cartilage after haemarthrosis have not been completely elucidated in haemophilic arthropathy. Insights into the pathophysiological mechanisms of blood-induced joint damage mainly derived from histological, inflammatory and biochemical investigations. A structure-function relationship is another reasonable way to determine the joint overall health status. Cartilage, a viscoelastic connective tissue, is at least a biphasic material that should also work under minimal friction. Pendulum friction tester measures the mechanical aspects of joint lubrication and quantifies the biotribological properties of the joint. Indentation test is an in situ method characterizing the biomechanical properties of the cartilage. Gross, biotribological and biomechanical properties were determined in a rabbit model of experimental haemarthrosis. A sample of 1 mL of fresh autologous blood was injected in the left knee of rabbit's joint twice weekly for four consecutive weeks. The right knee and animals in the control group were left untreated. After 8 days, joint perimeter, biotribological and biomechanical tests were performed. In a consistent manner, all data showed detrimental effects of the blood on the overall cartilage function under loading. Non-weight bearing and early blood aspiration seem wise to be considered after haemarthrosis.

The acutely ACL injured knee assessed by MRI: changes in joint fluid, bone marrow lesions, and cartilage during the first year

OBJECTIVES

To investigate changes in the knee during the first year after acute rupture of the anterior cruciate ligament (ACL) of volumes of joint fluid (JF), bone marrow lesions (BMLs), and cartilage volume (VC), and cartilage thickness (ThCcAB) and cartilage surface area (AC). To identify factors associated with these changes.

METHODS

Fifty-eight subjects (mean age 26 years, 16 women) with an ACL rupture to a previously un-injured knee were followed prospectively using a 1.5T MR imager at baseline (within 5 weeks from injury), 3 months, 6 months, and 1 year. Thirty-four subjects were treated with ACL reconstruction followed by a structured rehabilitation program and 24 subjects were treated with structured rehabilitation only. Morphometric data were acquired from computer-assisted segmentation of MR images. Morphometric cartilage change was reported as mean change divided by the standard deviation of change (standard response mean, SRM).

RESULTS

JF and BML volumes gradually decreased over the first year, although BML persisted in 62% of the knees after 1 year. One year after the ACL injury, a reduction of VC, AC and ThCcAB (SRM -0.440 or greater) was found in the trochlea femur (TrF), while an increase of VC and ThCcAB was found in the central medial femur (cMF) (SRM greater than 0.477). ACL reconstruction was directly and significantly related to increased JF volume at 3 and 6 months (P<0.001), BML volume at 6 months (P=0.031), VC and ThCcAB in cMF (P<0.002) and decreased cartilage area in TrF (P=0.010) at 12 months.

CONCLUSION

Following an acute ACL tear, cMF and TrF showed the greatest consistent changes of cartilage morphometry. An ACL reconstruction performed within a mean of 6 weeks from injury was associated with increased ThCcAB and VC in cMF and decreased AC in TrF, compared to knees treated without reconstruction. This may suggest a delayed structural restitution in ACL reconstructed knees.

Effect of blood on the morphological, biochemical and biomechanical properties of engineered cartilage

The use of autologous chondrocytes seeded onto a biological scaffold represents a current valid tool for cartilage repair. However, the effect of the contact of blood to the engineered construct is unknown. The aim of this work was to investigate in vitro the effect of blood on the morphological, biochemical and biomechanical properties of engineered cartilage. Articular chondrocytes were enzymatically isolated from swine joints, expanded in monolayer culture and seeded onto collagen membranes for 2 weeks. Then, the seeded membranes were placed for 3 days in contact with peripheral blood, which was obtained from animals of the same species and diluted with a standard medium. As controls, some samples were left in the standard medium. After the 3 days' contact, some samples were retrieved for analysis; others were returned to standard culture conditions for 21 additional days, in order to investigate the "long-term effect" of the blood contact. Upon retrieval, all seeded samples showed increasing sizes and weights over time. However, the samples exposed to blood presented lower values with respect to the controls. Biochemical evaluation demonstrated a reduction in the mitochondrial activity due to blood contact at the early culture time (3 days post blood contact), followed by a partial recovery at the longer culture time (21 days post blood contact). Histological evaluation demonstrated evident cartilage-like matrix production for both groups. Biomechanical data showed a reduction of the values, followed by stabilization, regardless of the presence of blood. Based on the data obtained in this study, we can conclude that blood contact affects the chondrocyte activity and determines a delay in the dimensional growth of the engineered cartilage; however, at the experimental times utilized in this study, this delay did not affect the histological pattern and the biomechanical properties of the construct.

Exposure of human cartilage tissue to low concentrations of blood for a short period of time leads to prolonged cartilage damage: an in vitro study

OBJECTIVE

Joint bleeding, or hemarthrosis, leads in time to severe joint damage. This study was carried out to test the in vitro thresholds of exposure time and concentration that lead to irreversible joint damage, to add to the discussion on the usefulness of aspiration of the joint after a hemorrhage.

METHODS

Explants of healthy human articular cartilage tissue were cultured in the presence or absence of 50% (volume/volume) blood for 1, 2, 3, or 4 days or in the presence of 0%, 5%, 10%, 20%, 30%, or 50% (v/v) blood for 4 days, followed by a 12-day period of recovery after withdrawal of blood. The effect of blood exposure on cartilage was determined by measuring the rate of proteoglycan synthesis as well as the release and content of cartilage matrix proteoglycans and the activity of matrix metalloproteinases.

RESULTS

Exposure of cartilage to 50% (v/v) blood led to adverse changes that were largely independent of the exposure time. The adverse effects persisted after an initial exposure of up to or exceeding 2 days. Exposure of cartilage to increasing concentrations of blood for 4 days led to concentration-dependent adverse changes. These effects persisted when the concentration equaled or exceeded 10% (v/v) blood. Moreover, after 2 days of exposure to a blood load of 10% (v/v), the adverse effects on cartilage were not reversible.

CONCLUSION

A 2-day exposure of cartilage in vitro to 10% (v/v) blood leads to prolonged impairment of joint cartilage. This suggests that aspiration of blood from the joint within 2 days after hemarthrosis should be considered to prevent blood-induced joint damage in the long term.