212 EVALUATION OF THE EFFICACY OF IL-1R ANTAGONISTS IN HUMAN CARTILAGE DEGRADATION EX VIVO

Osteoarthritis (OA) is the most common rheumatic disease, characterized by progressive articular cartilage degradation. Raman spectroscopy (RS) has been recently proposed as a label-free tool to detect molecular changes in musculoskeletal tissues. We used cartilage samples derived from human femoral heads to perform an ex vivo study of different Raman signals and ratios, related to major and minor molecular components of articular cartilage, hereby proposed as candidate optical biomarkers for OA. Validation was performed against the radiological Kellgren–Lawrence (K-L) grading system, as a gold standard, and cross-validated against sulfated glycosaminoglycans (sGAGs) and total collagens (Hyp) biochemical contents. Our results showed a significant decrease in sGAGs (SGAGs, A1063 cm−1/A1004 cm−1) and proteoglycans (PGs, A1375 cm−1/A1004 cm−1) and a significant increase in collagen disorganization (ColD/F, A1245 cm−1/A1270 cm−1), with OA severity. These were correlated with sGAGs or Hyp contents, respectively. Moreover, the SGAGs/HA ratio (A1063 cm−1/A960 cm−1), representing a functional matrix, rich in proteoglycans, to a mineralized matrix-hydroxyapatite (HA), was significantly lower in OA cartilage (K-L I vs. III–IV, p < 0.05), whilst the mineralized to collagenous matrix ratio (HA/Col, A960 cm−1/A920 cm−1) increased, being correlated with K-L. OA samples showed signs of tissue mineralization, supported by the presence of calcium crystals-related signals, such as phosphate, carbonate, and calcium pyrophosphate dihydrate (MGP, A960 cm−1/A1004 cm−1, MGC, A1070 cm−1/A1004 cm−1 and A1050 cm−1/A1004 cm−1). Finally, we observed an increase in lipids ratio (IL, A1450 cm−1/A1670 cm−1) with OA severity. As a conclusion, we have described the molecular fingerprint of hip cartilage, validating a panel of optical biomarkers and the potential of RS as a complementary diagnostic tool for OA.

Download Full-text

New Therapeutic Strategies for Osteoarthritis by Targeting Sialic Acid Receptors

Biomolecules ◽

10.3390/biom10040637 ◽

2020 ◽

Vol 10 (4) ◽

pp. 637 ◽

Cited By ~ 3

Author(s):

Paula Carpintero-Fernandez ◽

Marta Varela-Eirin ◽

Alessandra Lacetera ◽

Raquel Gago-Fuentes ◽

Eduardo Fonseca ◽

...

Keyword(s):

Articular Cartilage ◽

Ex Vivo ◽

Molecular Model ◽

Cartilage Degradation ◽

Degenerative Joint Disease ◽

Joint Disease ◽

Novel Therapy ◽

Human Cartilage ◽

Sialic Acid Receptors ◽

Cartilage Breakdown

Osteoarthritis (OA) is the most common degenerative joint disease characterized by articular cartilage degradation and joint degeneration. The articular cartilage is mainly formed by chondrocytes and a collagen-proteoglycan extracellular matrix that contains high levels of glycosylated proteins. It was reported that the shift from glycoproteins containing α-2,6-linked sialic acids to those that contain α-2,3 was associated with the onset of common types of arthritis. However, the pathophysiology of α-2,3-sialylation in cartilage has not been yet elucidated. We show that cartilage from osteoarthritic patients expresses high levels of the α-2,3-sialylated transmembrane mucin receptor, known as podoplanin (PDPN). Additionally, the Maackia amurensis seed lectin (MASL), that can be utilized to target PDPN, attenuates the inflammatory response mediated by NF-kB activation in primary chondrocytes and protects human cartilage breakdown ex vivo and in an animal model of arthritis. These findings reveal that specific lectins targeting α-2,3-sialylated receptors on chondrocytes might effectively inhibit cartilage breakdown. We also present a computational 3D molecular model for this interaction. These findings provide mechanistic information on how a specific lectin could be used as a novel therapy to treat degenerative joint diseases such as osteoarthritis.

Download Full-text

The Hexosamine Biosynthetic Pathway as a Therapeutic Target after Cartilage Trauma: Modification of Chondrocyte Survival and Metabolism by Glucosamine Derivatives and PUGNAc in an Ex Vivo Model

International Journal of Molecular Sciences ◽

10.3390/ijms22147247 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7247

Author(s):

Jana Riegger ◽

Julia Baumert ◽

Frank Zaucke ◽

Rolf E. Brenner

Keyword(s):

Biosynthetic Pathway ◽

Ex Vivo ◽

Type Ii Collagen ◽

Cartilage Explants ◽

Uridine Diphosphate ◽

Cell Protection ◽

Ex Vivo Model ◽

Human Cartilage ◽

Hexosamine Biosynthetic Pathway ◽

Cellular Processes

The hexosamine biosynthetic pathway (HBP) is essential for the production of uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), the building block of glycosaminoglycans, thus playing a crucial role in cartilage anabolism. Although O-GlcNAcylation represents a protective regulatory mechanism in cellular processes, it has been associated with degenerative diseases, including osteoarthritis (OA). The present study focuses on HBP-related processes as potential therapeutic targets after cartilage trauma. Human cartilage explants were traumatized and treated with GlcNAc or glucosamine sulfate (GS); PUGNAc, an inhibitor of O-GlcNAcase; or azaserine (AZA), an inhibitor of GFAT-1. After 7 days, cell viability and gene expression analysis of anabolic and catabolic markers, as well as HBP-related enzymes, were performed. Moreover, expression of catabolic enzymes and type II collagen (COL2) biosynthesis were determined. Proteoglycan content was assessed after 14 days. Cartilage trauma led to a dysbalanced expression of different HBP-related enzymes, comparable to the situation in highly degenerated tissue. While GlcNAc and PUGNAc resulted in significant cell protection after trauma, only PUGNAc increased COL2 biosynthesis. Moreover, PUGNAc and both glucosamine derivatives had anti-catabolic effects. In contrast, AZA increased catabolic processes. Overall, “fueling” the HBP by means of glucosamine derivatives or inhibition of deglycosylation turned out as cells and chondroprotectives after cartilage trauma.

Download Full-text

Inhibition by pepstatin of human cartilage degradation

Biochemical Journal ◽

10.1042/bj1270443 ◽

1972 ◽

Vol 127 (2) ◽

pp. 443-444 ◽

Cited By ~ 37

Author(s):

J T Dingle ◽

A J Barrett ◽

A R Poole ◽

P Stovin

Keyword(s):

Cartilage Degradation ◽

Human Cartilage

Download Full-text

Characterization of Ex Vivo–Generated Bovine and Human Cartilage by Immunohistochemical, Biochemical, and Magnetic Resonance Imaging Analyses

Tissue Engineering Part A ◽

10.1089/ten.tea.2009.0717 ◽

2010 ◽

Vol 16 (7) ◽

pp. 2183-2196 ◽

Cited By ~ 17

Author(s):

Ashleigh E. Nugent ◽

David A. Reiter ◽

Kenneth W. Fishbein ◽

Denise L. McBurney ◽

Travis Murray ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Ex Vivo ◽

Resonance Imaging ◽

Human Cartilage

Download Full-text

AB0099 COCULTURE OF SYNOVIAL MEMBRANE AND CARTILAGE: A POTENTIAL HUMAN EX VIVO CARTILAGE DEGRADATION MODEL

10.1136/annrheumdis-2019-eular.2159 ◽

2019 ◽

Author(s):

Johanna Mucke ◽

Victoria Warzynski ◽

Ellen Bleck ◽

Thomas Pauly ◽

Tim Claßen ◽

...

Keyword(s):

Synovial Membrane ◽

Ex Vivo ◽

Cartilage Degradation ◽

Degradation Model ◽

And Cartilage

Download Full-text

Cartilage-gut-microbiome axis: a new paradigm for novel therapeutic opportunities in osteoarthritis

RMD Open ◽

10.1136/rmdopen-2019-001037 ◽

2019 ◽

Vol 5 (2) ◽

pp. e001037 ◽

Cited By ~ 11

Author(s):

Jean-Marie Berthelot ◽

Jérémie Sellam ◽

Yves Maugars ◽

Francis Berenbaum

Keyword(s):

Gut Microbiota ◽

Gut Microbiome ◽

Cartilage Degradation ◽

Low Grade ◽

New Paradigm ◽

Healthy Human ◽

Human Cartilage ◽

Intact Cartilage ◽

Low Grade Inflammation

DNA of gut microbiota can be found in synovium of osteoarthritis and rheumatoid arthritis. This finding could result from the translocation of still alive bacteria from gut to joints through blood, since the diversified dormant microbiota of healthy human blood can be transiently resuscitated in vitro. The recent finding of gut microbiome in human cartilage, which differed between osteoarthritis and controls, suggests that a similar trafficking of dead or alive bacteria from gut microbiota physiologically occurs between gut and epiphysial bone marrow. Subchondral microbiota could enhance cartilage healing and transform components of deep cartilage matrix in metabolites with immunosuppressive properties. The differences of microbiome observed between hip and knee cartilage, either in osteoarthritis or controls, might be the counterpart of subtle differences in chondrocyte metabolism, themselves in line with differences in DNA methylation according to joints. Although bacteria theoretically cannot reach chondrocytes from the surface of intact cartilage, some bacteria enter the vascular channels of the epiphysial growth cartilage in young animals, whereas others can infect chondrocytes in vitro. In osteoarthritis, the early osteochondral plate angiogenesis may further enhance the ability of microbiota to locate close to the deeper layers of cartilage, and this might lead to focal dysbiosis, low-grade inflammation, cartilage degradation, epigenetic changes in chondrocytes and worsening of osteoarthritis. More studies on cartilage across different ethnic groups, weights, and according to age, are needed, to confirm the silent presence of gut microbiota close to human cartilage and better understand its physiologic and pathogenic significance.

Download Full-text

EZH2 inhibition reduces cartilage loss and functional impairment related to osteoarthritis

Scientific Reports ◽

10.1038/s41598-020-76724-9 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Lyess Allas ◽

Sybille Brochard ◽

Quitterie Rochoux ◽

Jules Ribet ◽

Cleo Dujarrier ◽

...

Keyword(s):

Functional Disability ◽

Ex Vivo ◽

Cartilage Degradation ◽

Motor Functions ◽

Methyl Transferase ◽

Expression Of Genes ◽

Medial Meniscectomy ◽

The Impact

Abstract Histone methyltransferase EZH2 is upregulated during osteoarthritis (OA), which is the most widespread rheumatic disease worldwide, and a leading cause of disability. This study aimed to assess the impact of EZH2 inhibition on cartilage degradation, inflammation and functional disability. In vitro, gain and loss of EZH2 function were performed in human articular OA chondrocytes stimulated with IL-1β. In vivo, the effects of EZH2 inhibition were investigated on medial meniscectomy (MMX) OA mouse model. The tissue alterations were assayed by histology and the functional disabilities of the mice by actimetry and running wheel. In vitro, EZH2 overexpression exacerbated the action of IL-1β in chondrocytes increasing the expression of genes involved in inflammation, pain (NO, PGE2, IL6, NGF) and catabolism (MMPs), whereas EZH2 inhibition by a pharmacological inhibitor, EPZ-6438, reduced IL-1β effects. Ex vivo, EZH2 inhibition decreased IL-1β-induced degradation of cartilage. In vivo, intra-articular injections of the EZH2 inhibitor reduced cartilage degradation and improved motor functions of OA mice. This study demonstrates that the pharmacological inhibition of the histone methyl-transferase EZH2 slows the progression of osteoarthritis and improves motor functions in an experimental OA model, suggesting that EZH2 could be an effective target for the treatment of OA by reducing catabolism, inflammation and pain.

Download Full-text