The proteasome inhibitor bortezomib drastically affects inflammation and bone disease in adjuvant‐induced arthritis in rats

Abstract

Objective. To explore the effect of bortezomib in splenocytes and fibroblast-like synoviocytes (FLS) and its in vivo potency in a rat model of adjuvant-induced arthritis (AIA), which resembles human rheumatoid arthritis (RA).Methods. AIA was induced with Freund's complete adjuvant. Splenocyte and FLS proliferation and apoptosis were measured by radioactivity incorporation and flow cytometry, respectively. The invasiveness of FLS from rats with AIA was tested in a Transwell system. The pattern of cytokine secretion was evaluated by cytometric bead array in splenocyte supernatants. Bortezomib was administered prophylactically or therapeutically, and arthritis was assessed clinically and histologically. Immunohistochemistry was performed for markers of inflammation and angiogenesis in joints.Hematologic and biochemical parameters were tested in peripheral blood (PB). Representative animals were examined by computed tomography (CT) scanning before and after bortezomib administration. The expression of Toll-like receptor 2 (TLR-2), TLR-3, and TLR-4 in PB and FLS was measured by real-time polymerase chain reaction, and alterations in specific cell populations in PB and spleen were determined by flow cytometry.Results. In vitro, bortezomib exhibited significant inhibitory and proapoptotic activity in splenocytes and FLS from rats with AIA, altered the inflammatory cytokine pattern, and reduced the invasiveness of FLS from rats with AIA. In vivo, bortezomib significantly ameliorated disease severity. Remission was associated with improved histology and decreased expression of CD3, CD79a, CD11b, cyclooxygenase 1, and factor VIII in target tissues as well as down-regulation of TLR expression in PB and cultured FLS. CT scanning demonstrated a bone healing effect after treatment.Conclusion. Our findings suggest that bortezomib affects AIA in a pleiotropic manner and that this drug may be effective in RA.

Proteasome Inhibition Reduces Proliferation, Collagen Expression, and Inflammatory Cytokine Production in Nasal Mucosa and Polyp Fibroblasts

“…In keeping with the blocking effects of MG262 on the cell cycle, MG262 inhibited the proliferation (DNA replication) of nasal fibroblasts. These results concur with the marked inhibition of cell proliferation after the incubation of fibroblast-like synoviocytes with bortezomib, at the same concentration (10 nM) used in our study (Yannaki et al, 2010).…”

“…The kinetics and sensitivity (IC 50 ) of MG262 and bortezomib inhibition was similar to those reported for bortezomib in cancer cell lines (Hideshima et al, 2001;Codony-Servat et al, 2006). Our results concur with those reported in human pulmonary fibroblasts using the proteasome inhibitor benzyloxycarbonylleucyl-leucyl-leucine aldehyde (MG132) (You and Park, 2011) and bortezomibtreated rat fibroblast-like synoviocytes (Yannaki et al, 2010), but contrast with those of Fineschi et al (2006Fineschi et al ( , 2008. The latter, using a similar experimental approach and analytical method, found that MG262 and proteasome inhibitor I decreased the viability of human dermal fibroblasts only when used at very high (micromolar) concentrations after 72 h of culture (Fineschi et al, 2006).…”

“…Owing to the key role of NF-B in multiple inflammatory diseases, the use of proteasome inhibitors has been proposed as an anti-inflammatory strategy for treating non-neoplastic diseases (Wang and Maldonado, 2006;Meiners et al, 2008). They have been shown to reduce the inflammatory response in experimental animal models of hypertension , arthritis (Palombella et al, 1998;Yannaki et al, 2010), colitis (Schmidt et al, 2010), and asthma (Elliott et al, 1999). Proteasome inhibitors have also demonstrated antifibrotic effects on animal models of cardiac fibrosis (Meiners et al, 2004), muscle atrophy (Carmignac et al, 2011), and lung and skin fibrosis (Mutlu et al, 2012).…”

Therapeutic Potential of the Proteasome Inhibitor Bortezomib on Titanium Particle-Induced Inflammation in a Murine Model

“…Bzb, a modified dipeptidyl boronic acid that reversibly inhibits the chymotrypsinlike activity of the 26S proteasome, is the first proteasome inhibitor approved by the FDA for clinical use to treat multiple myeloma [15]. In addition to its anti-tumor effects, Bzb has also been shown to affect inflammation of mimicked rheumatoid arthritis in animal models [16,17], but little is known about the effects of Bzb on the expression of inflammation after TJR. Wear debris generated around implanted prostheses is well accepted as the major initiating event in the development of inflammatory osteolysis and subsequent aseptic loosening.…”

Emerging immunotherapies for rheumatoid arthritis

“…51 When used in animal RA models there was a marked reduction in disease severity, inflammatory cytokines and fibroblast like synoviocytes became more pro-apoptopic as well as less invasive. 52,53 Furthermore T-cells from RA patients when treated exvivo with bortezomib were increasingly anergic, pro-apoptopic, and had a reduced inflammatory cytokine profile. 54 Furthermore in SLE animal models bortezomib slows disease onset and ameliorates disease phenotype.…”