Antigen-specific expansion of TCR Vbeta3+ CD4+ T cells in the early stage of collagen-induced arthritis and its arthritogenic role in DBA/1J mice

Oxidative stress modulating nanomaterials and their biochemical roles in nanomedicine

Many pathological conditions are predominantly associated with oxidative stress, arising from reactive oxygen species (ROS); therefore, the modulation of redox activities has been a key strategy to restore normal tissue functions. Current approaches involve establishing a favorable cellular redox environment through the administration of therapeutic drugs and redox-active nanomaterials (RANs). In particular, RANs not only provide a stable and reliable means of therapeutic delivery but also possess the capacity to finely tune various interconnected components, including radicals, enzymes, proteins, transcription factors, and metabolites. Here, we discuss the roles that engineered RANs play in a spectrum of pathological conditions, such as cancer, neurodegenerative diseases, infections, and inflammation. We visualize the dual functions of RANs as both generator and scavenger of ROS, emphasizing their profound impact on diverse cellular functions. The focus of this review is solely on inorganic redox-active nanomaterials (inorganic RANs). Additionally, we deliberate on the challenges associated with current RANs-based approaches and propose potential research directions for their future clinical translation.

Suppressive effect of an orally active MEK1/2 inhibitor in two different animal models for rheumatoid arthritis: a comparison with leflunomide

OBJECTIVE AND DESIGN

To examine the effects of a mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 1/2-inhibitor, JTP-74057, on inflammatory arthritis development, and compare its anti-arthritic effect with leflunomide.

MATERIALS

Human, mouse, and rat peripheral blood mononuclear cells (PBMCs) were used. Lewis rats and DBA/1J mice were used for animal models.

TREATMENT

JTP-74057 was tested between 0.1-100 nM in in-vitro studies. JTP-74057 (0.01-0.3 mg/kg) and leflunomide (2-10 mg/kg) were administered orally in vivo.

METHODS

PBMCs were stimulated with lipopolysaccharide. Adjuvant-induced arthritis (AIA) and type II collagen-induced arthritis (CIA) was induced in Lewis rats or DBA1/J mice, respectively.

RESULTS

JTP-74057 blocked tumor necrosis factor-α and interleukin-6 production from PBMCs. AIA and CIA development were suppressed almost completely by 0.1 mg/kg of JTP-74057 or 10 mg/kg of leflunomide. In the CIA, JTP-74057, but not leflunomide, suppressed collagen-reactive T-cell proliferation ex vivo, whereas leflunomide, but not JTP-74057, suppressed anti-collagen antibody production.

CONCLUSIONS

JTP-74057 exerts potent anti-arthritic effects with a different profile from leflunomide, suggesting that JTP-74057 may be useful as a new therapeutic reagent in the treatment of rheumatoid arthritis.

Bortezomib attenuates murine collagen-induced arthritis

OBJECTIVES

Nuclear factor kappa B (NF-kappaB) is a major regulator of pivotal proinflammatory cytokines in the pathogenesis of rheumatoid arthritis (RA). Bortezomib inhibits NF-kappaB activation by blocking the degradation of the NF-kappaB inhibitor, I-kappaB. In this study, the efficacy of bortezomib on murine collagen-induced arthritis (CIA) was investigated.

METHODS

Thirty-five male DBA/1 mice were divided into five groups. All mice except controls were injected with type II collagen. Mice in the bortezomib-treated groups were injected intraperitoneally with 0.01, 0.1 and 1 mg/kg bortezomib twice a week for 2 weeks. Controls and mice in the untreated group were also injected intraperitoneally with phosphate-buffered saline in the same manner. Arthritis score and paw thickness were measured and histopathological assessment of joint sections was performed. The expression of proinflammatory cytokines and enzymes was evaluated by immunohistochemical staining. Joint destruction was confirmed using three-dimensional micro-computerised tomography (CT). Blood cells were counted and liver and kidney functions were monitored.

RESULTS

Bortezomib significantly attenuated the severity of arthritis and histopathological findings in CIA mice. The expression of tumour necrosis factor alpha, IL-1beta, IL-6, matrix metalloproteinase 3, cyclooxygenase 2 and inducible nitric oxide synthase decreased in bortezomib-treated mice compared with untreated mice. In addition, micro-CT confirmed that bortezomib reduced joint destruction. No adverse effects in blood cells, liver or kidneys were observed with bortezomib treatment.

CONCLUSIONS

These data suggest that bortezomib may play an anti-inflammatory role in the pathophysiology of RA and serve as a new therapeutic modality for RA.

Adiponectin mitigates the severity of arthritis in mice with collagen-induced arthritis

OBJECTIVE

Adiponectin (AD) is considered an inflammation modulator. In this study, we investigated the effect of AD on rheumatoid arthritis (RA) using a collagen-induced arthritis (CIA) mouse model and RA synovial fibroblasts (RASF).

METHODS

Fifteen DBA/1 mice were divided into three groups. All mice, except the control group, were injected with type II collagen. AD was intra-articularly injected in the left hind legs after arthritis development (the AD-treated group). The severity of the arthritis was measured using an arthritis score and paw thickness. A histopathological assessment of joint sections was performed by haematoxylin/eosin (H&E) staining. Tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, and matrix metalloproteinase (MMP)-3 expression was evaluated by immunohistochemical staining in the CIA mice. Synovial tissue was obtained from four RA patients during total joint replacement. RASF cultures were established from this tissue. RASF were pretreated with AD and stimulated by TNFalpha or IL-1beta. TNFalpha, IL-1beta, IL-6, and MMP-3 production was measured by enzyme-linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR). RASF proliferation was evaluated using the MTT assay.

RESULTS

AD significantly mitigated the severity of the arthritis and histopathological findings indicative of RA in CIA mice. TNFalpha, IL-1beta, and MMP-3 expression decreased, but IL-6 expression in AD-treated joint tissues increased. Moreover, AD reduced TNFalpha, IL-1beta, and MMP-3 expression in stimulated RASF and increased IL-6 expression in IL-1beta-stimulated RASF. AD significantly inhibited IL-1beta-induced RASF proliferation, despite increased IL-6 expression.

CONCLUSION

These data suggest that AD may play an anti-inflammatory role in the pathophysiology of RA.

Type II collagen autoimmunity in a mouse model of human rheumatoid arthritis

Type II collagen (CII) is expressed exclusively in the joint articular. Although the relationship between anti-CII immunity and human rheumatoid arthritis (RA) has been studied for a long time, definitive conclusions have not been reached. CII, as an autoantigen, has been studied extensively in small animal models, such as mice, and the collagen-induced arthritis (CIA) model has increased our understanding of the pathogenesis of human RA. In the present report, we summarize the available information on anti-CII immunity and discuss recent updates regarding pathogenesis in the CIA model, including the role of Th17 cells.

FR180204, a novel and selective inhibitor of extracellular signal-regulated kinase, ameliorates collagen-induced arthritis in mice

Extracellular signal-regulated kinase (ERK), a serine/threonine protein kinase of the mitogen-activated protein kinase superfamily, is activated by various stimuli in inflammatory cells. We recently described FR180204 (5-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)-1H-pyrazolo[3,4-c]pyridazin-3-amine), a novel selective ERK inhibitor. In this paper, we investigated the effect of FR180204 on collagen-induced arthritis (CIA) in DBA/1 mice, an animal model of rheumatoid arthritis (RA) mediated by type II collagen (CII)-reactive T cells and anti-CII antibodies. Preventive administration of FR180204 (100 mg/kg, i.p., b.i.d.) significantly ameliorated the clinical arthritis and body weight loss occurring in the CIA mice. Further, FR180204-treated mice showed a significant decrease in plasma anti-CII antibody levels (62%). FR180204 also attenuated delayed-type hypersensitivity in CII-immunized DBA/1 mice, an inflammatory response elicited by CII-reactive T cells, in a dose-dependent manner (52 and 62% inhibition at 32 and 100 mg/kg, respectively). Moreover, FR180204 inhibited in vitro CII-induced proliferation of lymph node cells prepared from CII-immunized mice, in which CII-specific T cells are known to undergo specific proliferation. In conclusion, our results suggest that ERK regulates both the cell-mediated and humoral immune responses in the development of CIA. ERK inhibitors may be useful as therapeutic reagents for the treatment of RA.