Proteomic Analysis of Synovial Fibroblasts and Articular Chondrocytes Co-Cultures Reveals Valuable VIP-Modulated Inflammatory and Degradative Proteins in Osteoarthritis

Abstract

Osteoarthritis (OA) is the most common musculoskeletal disorder causing a great disability and a reduction in the quality of life. In OA, articular chondrocytes (AC) and synovial fibroblasts (SF) release innate-derived immune mediators that initiate and perpetuate inflammation, inducing cartilage extracellular matrix (ECM) degradation. Given the lack of therapies for the treatment of OA, in this study, we explore biomarkers that enable the development of new therapeutical approaches. We analyze the set of secreted proteins in AC and SF co-cultures by stable isotope labeling with amino acids (SILAC). We describe, for the first time, 115 proteins detected in SF-AC co-cultures stimulated by fibronectin fragments (Fn-fs). We also study the role of the vasoactive intestinal peptide (VIP) in this secretome, providing new proteins involved in the main events of OA, confirmed by ELISA and multiplex analyses. VIP decreases proteins involved in the inflammatory process (CHI3L1, PTX3), complement activation (C1r, C3), and cartilage ECM degradation (DCN, CTSB and MMP2), key events in the initiation and progression of OA. Our results support the anti-inflammatory and anti-catabolic properties of VIP in rheumatic diseases and provide potential new targets for OA treatment.

RNA-Seq of Dermal Fibroblasts from Patients with Hypermobile Ehlers–Danlos Syndrome and Hypermobility Spectrum Disorders Supports Their Categorization as a Single Entity with Involvement of Extracellular Matrix Degrading and Proinflammatory Pathomechanisms

“…Notably, the dysregulated gene expression signature of hEDS/HSD cells is consistent with previous reported gene expression studies in normal meniscus cells, synovial fibroblasts, and articular chondrocytes treated with different proinflammatory factors including cytokines, interleukins, and FN-fs [37][38][39]. These proinflammatory stimuli have been demonstrated to induce transcriptional changes in many genes found differentially expressed also in our patients' fibroblasts.…”

Matrix Metalloproteinases Inhibition by Doxycycline Rescues Extracellular Matrix Organization and Partly Reverts Myofibroblast Differentiation in Hypermobile Ehlers-Danlos Syndrome Dermal Fibroblasts: A Potential Therapeutic Target?

“…These danger molecules promote maladaptive responses by inducing the expression of proinflammatory mediators and cytokines, nitric oxide, along with proteinases (including MMPs) that in turn, degrade further ECM components, creating a degradative and inflammatory feedback loop [37][38][39][40][41]. For instance, high amounts of FN-fs have been detected in cartilage and synovial fluid of OA patients and in vitro stimulations of human articular chondrocytes and synovial fibroblasts with FN-fs recapitulate several features of the pathological phenotype [39,[42][43][44]. Similarly, TNC-fs act as endogenous inducers of cartilage ECM degradation by stimulating cytokines and MMPs production through binding with toll-like receptor 4 and integrins including αvβ3 [45,46].…”

Using Macrophage Polarization in Human Platelet Lysate to Test the Immunomodulatory Potential of Cells for Clinical Use

“…Co-culture models have been widely applied in OA research, mimicking joint microenvironments to study complex cell interactions [12]. These models can be exploited to elucidate cell-cell communication, unraveling OA pathogenesis and identifying potential therapeutic targets, and they include different combinations of articular cells and/or tissue explants, offering insights into OA's complexity [13][14][15]. Co-culture systems, including macrophages, are instead more focused on understanding OA-related inflammation and testing the ability of cell-based therapies to modulate the inflammatory state [10,16].…”