Vasoactive intestinal peptide exerts an osteoinductive effect in human mesenchymal stem cells.

Several neuropeptides present in bone tissues, produced by nerve fibers and bone cells, have been reported to play a role in regulating the fine-tuning of osteoblast and osteoclast functions to maintain bone homeostasis. This study aims to characterize the influence of the neuropeptide vasoactive intestinal peptide (VIP) on the differentiation process of human mesenchymal stem cells (MSCs) into osteoblasts and on their anabolic function. We describe the mRNA and protein expression profile of VIP and its receptors in MSCs as they differentiate into osteoblasts, suggesting the presence of an autocrine signaling pathway in these cells.

The Neuropeptide VIP Limits Human Osteoclastogenesis: Clinical Associations with Bone Metabolism Markers in Patients with Early Arthritis.

We aimed to evaluate the direct action of VIP on crucial molecules involved in human osteoclast differentiation and function. We also investigated the relationship between VIP serum levels and bone remodeling mediators in early arthritis patients. The expression of VIP receptors and osteoclast gene markers in monocytes and in vitro differentiated osteoclasts was studied by real-time PCR.

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

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.

Comparative Study of Senescent Th Biomarkers in Healthy Donors and Early Arthritis Patients. Analysis of VPAC Receptors and Their Influence.

Pro-inflammatory CD4CD28 T cells are characteristic of immunosenescence, but also of several autoimmune/inflammatory diseases. Vasoactive intestinal peptide (VIP) acts as an anti-inflammatory and immunomodulatory mediator on these cells. Our objective was to study the mutual influence between senescent Th cells and VIP axis in early arthritis (EA), comparing with non-EA donors.

Profile of Matrix-Remodeling Proteinases in Osteoarthritis: Impact of Fibronectin.

The extracellular matrix (ECM) is a complex and specialized three-dimensional macromolecular network, present in nearly all tissues, that also interacts with cell surface receptors on joint resident cells. Changes in the composition and physical properties of the ECM lead to the development of many diseases, including osteoarthritis (OA). OA is a chronic degenerative rheumatic disease characterized by a progressive loss of synovial joint function as a consequence of the degradation of articular cartilage, also associated with alterations in the synovial membrane and subchondral bone.

A Clinical Approach for the Use of VIP Axis in Inflammatory and Autoimmune Diseases.

The neuroendocrine and immune systems are coordinated to maintain the homeostasis of the organism, generating bidirectional communication through shared mediators and receptors. Vasoactive intestinal peptide (VIP) is the paradigm of an endogenous neuropeptide produced by neurons and endocrine and immune cells, involved in the control of both innate and adaptive immune responses. Exogenous administration of VIP exerts therapeutic effects in models of autoimmune/inflammatory diseases mediated by G-protein-coupled receptors (VPAC1 and VPAC2).

An Overview of VPAC Receptors in Rheumatoid Arthritis: Biological Role and Clinical Significance.

The axis comprised by the Vasoactive Intestinal Peptide (VIP) and its G protein-coupled receptors (GPCRs), VPAC1, and VPAC2, belong to the B1 family and signal through Gs or Gq proteins. VPAC receptors seem to preferentially interact with Gs in inflammatory cells, rather than Gq, thereby stimulating adenylate cyclase activity. cAMP is able to trigger various downstream pathways, mainly the canonical PKA pathway and the non-canonical cAMP-activated guanine nucleotide exchange factor (EPAC) pathway.

The Adipokine Network in Rheumatic Joint Diseases.

Rheumatic diseases encompass a diverse group of chronic disorders that commonly affect musculoskeletal structures. Osteoarthritis (OA) and rheumatoid arthritis (RA) are the two most common, leading to considerable functional limitations and irreversible disability when patients are unsuccessfully treated. Although the specific causes of many rheumatic conditions remain unknown, it is generally accepted that immune mechanisms and/or uncontrolled inflammatory responses are involved in their etiology and symptomatology.

Wnt and RUNX2 mediate cartilage breakdown by osteoarthritis synovial fibroblast-derived ADAMTS-7 and -12.

Failure of therapeutic approaches for the treatment of osteoarthritis (OA) based on the inhibition of metalloproteinases, might be because of their constitutive expression in homeostasis, together with their network complexity. The knowledge of this network would contribute to selective target pathological conditions. In this sense, blockade of mediators produced by neighbouring joint cells, such as synovial fibroblasts (SF), would prevent cartilage damage.

VIP impairs acquisition of the macrophage proinflammatory polarization profile.

This study tested the hypothesis that vasoactive intestinal peptide (VIP) is able to modify the macrophage inflammatory profile, thus supporting its therapeutic role in autoimmune diseases. Macrophages are innate immune cells that display a variety of functions and inflammatory profiles in response to the environment that critically controls their polarization. Deregulation between the pro- and anti-inflammatory phenotypes has been involved in different pathologies.

VIP and CRF reduce ADAMTS expression and function in osteoarthritis synovial fibroblasts.

ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family is known to play an important role in the pathogenesis of osteoarthritis (OA), working on aggrecan degradation or altering the integrity of extracellular matrix (ECM). Thus, the main purpose of our study was to define the role of vasoactive intestinal peptide (VIP) and corticotrophin-releasing factor (CRF), as immunoregulatory neuropeptides, on ADAMTS production in synovial fibroblasts (SF) from OA patients and healthy donors (HD). OA- and HD-SF were stimulated with pro-inflammatory mediators and treated with VIP or CRF.

The pathogenic Th profile of human activated memory Th cells in early rheumatoid arthritis can be modulated by VIP.

Unlabelled: Our aim is to study the behavior of memory Th cells (Th17, Th17/1, and Th1 profiles) from early rheumatoid arthritis (eRA) patients after their in vitro activation/expansion to provide information about its contribution to RA chronicity. Moreover, we analyzed the potential involvement of vasoactive intestinal peptide (VIP) as an endogenous healing mediator. CD4(+)CD45RO(+) T cells from PBMCs of HD and eRA were activated/expanded in vitro in the presence/absence of VIP.

Vasoactive intestinal peptide maintains the nonpathogenic profile of human th17-polarized cells.

The cytokine microenvironment modulates CD4 T cell differentiation causing the shift of naïve CD4 T cells into different cell subsets. This process is also regulated by modulators such as vasoactive intestinal peptide (VIP), a neuropeptide with known immunomodulatory properties on CD4 T cells that exert this action through specific receptors, vasoactive intestinal peptide receptor (VPAC)1 and VPAC2. Our results show that the pattern of VIP receptors expression ratio is modified during Th17 differentiation.

Urokinase plasminogen activator system in synovial fibroblasts from osteoarthritis patients: modulation by inflammatory mediators and neuropeptides.

Plasminogen activators are specific proteolytic enzymes implicated in a variety of basic biological processes. The expression of the urokinase plasminogen activator system components is increased in some human diseases, including osteoarthritis. We sought to study the effect of two components of the inflamed synovial microenvironment on this system, IL-1β and fibronectin fragments, elucidating whether corticotropin-releasing factor (CRF) and vasoactive intestinal peptide (VIP) neuropeptides modulate it, and analyzing the physiological consequences in joint destruction by measuring matrix metalloproteinases-9 and metalloproteinases-13 levels in osteoarthritis fibroblast-like synoviocytes.

VIP modulates IL-22R1 expression and prevents the contribution of rheumatoid synovial fibroblasts to IL-22-mediated joint destruction.

Rheumatoid arthritis (RA) and osteoarthritis are two rheumatic diseases whose progression is associated with a chronic synovitis. Fibroblast-like synoviocytes (FLS) have been shown to play a pivotal role in initiating and perpetuating inflammatory and destructive processes in the rheumatoid joint. Recently, the stimulating role of IL-22 has been reported on RA-FLS contribution to joint destruction by means of the increase of proliferation and matrix-metalloproteinase-1 (MMP-1) and alarmin S100A8/A9 production.

IL-22/IL-22R1 axis and S100A8/A9 alarmins in human osteoarthritic and rheumatoid arthritis synovial fibroblasts.

Objectives: Fibroblast-like synoviocytes (FLSs) are crucial players in the pathogenesis of synovitis in rheumatic diseases. Targeting FLS activation represents an approach to the development of therapeutic strategies. Our aim was to investigate whether the microenvironment of inflamed joints could modulate the expression of IL-22 and IL-22R1 on OA and RA FLSs.

Inflammatory mediators alter interleukin-17 receptor, interleukin-12 and -23 expression in human osteoarthritic and rheumatoid arthritis synovial fibroblasts: immunomodulation by vasoactive intestinal Peptide.

Aims: To assess the contribution of fibroblast-like synoviocytes (FLS) to the inflammatory joint microenvironment under different pathogenic stimuli and their potential to respond to interleukin (IL)-17 and to determine whether the neuroimmunomodulatory vasoactive intestinal peptide (VIP) is able to modulate IL-17 receptor (IL-17R) and related cytokines.

Methods: The effect of proinflammatory cytokines [tumor necrosis factor α (TNFα) and IL-17] and Toll-like receptor (TLR) ligands [poly(I:C) and lipopolysaccharide (LPS)] on IL-17R expression and IL-12 and IL-23 production was studied in osteoarthritis (OA)- and rheumatoid arthritis (RA)-FLS, involved in Th1/Th17 differentiation. The effect of VIP was also determined.

Effect of VIP on the balance between cytokines and master regulators of activated helper T cells.

CD4T helper cells are decisive in the struggle against pathogens and in maintaining immune homeostasis. Nevertheless, they also drive immune-mediated disease. Recently, emerging evidence suggests that seemingly committed Th cells possess plasticity and may convert into other types of effector cells.

Mapping the CRF-urocortins system in human osteoarthritic and rheumatoid synovial fibroblasts: effect of vasoactive intestinal peptide.

In addition to the brain and pituitary gland, the corticotrophin-releasing factor (CRF) system is expressed in peripheral tissues. In this study we characterize the expression of CRF, urocortins (UCN1, UCN2, and UCN3), and their receptors (CRFR1 and CRFR2) in osteoarthritis (OA) and rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS). Moreover, we analyze the vasoactive intestinal peptide (VIP) effect on the CRF system, as well as its physiological consequences on mediators of inflammatory/destructive processes.

RNA sensors in human osteoarthritis and rheumatoid arthritis synovial fibroblasts: immune regulation by vasoactive intestinal peptide.

Objective: The aim of this study was to analyze both the constitutive and induced expression and function of double-stranded RNA (dsRNA; Toll-like receptor 3 [TLR-3], retinoic acid-inducible gene I [RIG-I], and melanoma differentiation-associated gene 5 [MDA5]) and single-stranded RNA (ssRNA; TLR-7) receptors in osteoarthritis (OA) and rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS), by studying the transcription factors involved and the subsequent effects on antiviral interferon-β (IFNβ), the proinflammatory CXCL8 chemokine, and matrix metalloproteinase 3 (MMP-3). An additional goal was to study the effect of vasoactive intestinal peptide (VIP).

Methods: The expression of TLR-3, TLR-7, RIG-I, and MDA5 in cultured FLS was studied by reverse transcription-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), immunofluorescence, and Western blotting.

VIP reverses the expression profiling of TLR4-stimulated signaling pathway in rheumatoid arthritis synovial fibroblasts.

Since recent evidences point out the potential involvement of Toll-like receptors (TLRs) in the therapeutic effect of vasoactive intestinal peptide (VIP), the purpose of this study is to elucidate the role of VIP as a negative regulator of TLR-signaling. To this aim, we analyzed in fibroblast-like synoviocytes (FLS) from patients with rheumatoid arthritis (RA) or osteoarthritis (OA), the expression profile of TLR-pathway related molecules, as well as the alterations induced by LPS stimulation in RA-FLS and the effect of VIP treatment. Cultured FLS were obtained from patients with RA or OA.

Differential expression of vasoactive intestinal peptide and its functional receptors in human osteoarthritic and rheumatoid synovial fibroblasts.

Objective: Vasoactive intestinal peptide (VIP) has shown potent antiinflammatory effects in murine arthritis and ex vivo in human rheumatoid arthritis (RA) synovial cells. To investigate the potential endogenous participation of this system in the pathogenesis of RA, we analyzed the expression and regulation of VIP and its functional receptors in human fibroblast-like synoviocytes (FLS) from patients with osteoarthritis (OA) and patients with RA.

Methods: The expression of VIP was studied by reverse transcription-polymerase chain reaction (RT-PCR), enzyme immunoassay, and immunofluorescence in cultured FLS, and by immunohistochemical analysis in synovial tissue.

Vasoactive intestinal peptide regulates Th17 function in autoimmune inflammation.

An imbalance of pro-inflammatory and anti-inflammatory cytokines, autoreactive and inflammatory T helper 1 (Th1) cells, and regulatory T (Treg) cells results in the loss of immune tolerance and the subsequent appearance of inflammatory autoimmune diseases. On the other hand, hormones and neuropeptides are endogenous factors controlling the immune homeostasis that have been proposed as therapeutic agents in different autoimmune disorders. Among them, the vasoactive intestinal peptide (VIP) has been shown to downregulate the inflammatory response and to alter the Th1/Th2 balance in favor of anti-inflammatory Th2 immune responses.