Attenuation of collagen-induced arthritis in mice by salmon proteoglycan
Sayuri Yoshimura1, Krisana Asano1, Akio Nakane1
1Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan.
Abstract:
Rheumatoid arthritis (RA) is a serious autoimmune disease caused by chronic inflammation of connective tissues. The basic principle of RA treatment is aimed to reduce joint inflammation. Our previous studies demonstrated that salmon cartilage proteoglycan (PG) suppresses excess inflammation in different mouse inflammatory diseases. In this study, we investigated the prophylactic effect of PG on the progression of RA using an experimental mouse model, collagen-induced arthritis (CIA). Clinical and histological severity of CIA was attenuated by daily oral administration of PG. In the joints of PG-administered mice, infiltration of macrophages and neutrophils and also osteoclast accumulation were limited. In comparison to nonadministered mice, anti-collagen antibodies in the sera of PG-administered mice did not alter. On the other hand, local expression of interleukin-17A (IL-17A), IL-6, IL-1 β, interferon- γ (IFN- γ), C-C chemokine ligand 2 (CCL2), C-X-C chemokine ligand 1 (CXCL1), and CXCL2 in the joints of PG-administered mice decreased. Moreover, in the response of type II collagen- (CII-) restimulation ex vivo, IL-17A and IFN- γ production by splenocytes from PG-administered mice was less than that of control mice. These data suggested that daily ingested PG attenuated CIA pathogenesis by modulating immune response of splenocytes to CII stimulation and local production inflammatory cytokines and chemokines in the joints.
Insights
Salmon cartilage proteoglycan (PG) shows promise in treating rheumatoid arthritis (RA). Daily oral PG intake reduced inflammation and joint damage in a collagen-induced arthritis (CIA) mouse model.
Area of Science:
- Immunology
- Rheumatology
- Biochemistry
Background:
- Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by joint inflammation.
- Current RA treatments aim to reduce inflammation, but novel therapeutic strategies are needed.
- Salmon cartilage proteoglycan (PG) has demonstrated anti-inflammatory properties in previous studies.
Purpose of the Study:
- To investigate the prophylactic effect of salmon cartilage proteoglycan (PG) on the progression of rheumatoid arthritis (RA).
- To evaluate PG's impact on clinical and histological severity in a collagen-induced arthritis (CIA) mouse model.
Main Methods:
- A collagen-induced arthritis (CIA) mouse model was used to study RA progression.
- Mice were administered with salmon cartilage proteoglycan (PG) daily via oral administration.
- Clinical and histological assessments were performed to evaluate disease severity.
- Immune cell infiltration, antibody levels, and local cytokine/chemokine expression in joints were analyzed.
- Splenocyte responses to type II collagen (CII) restimulation ex vivo were measured.
Main Results:
- Daily oral administration of PG significantly attenuated the clinical and histological severity of CIA.
- PG treatment limited the infiltration of macrophages, neutrophils, and osteoclasts in the joints.
- Serum anti-collagen antibodies remained unchanged in PG-administered mice.
- Local expression of key inflammatory mediators, including IL-17A, IL-6, IL-1β, IFN-γ, CCL2, CXCL1, and CXCL2, was decreased in the joints of PG-treated mice.
- Ex vivo restimulation with CII showed reduced production of IL-17A and IFN-γ by splenocytes from PG-administered mice.
Conclusions:
- Daily oral intake of salmon cartilage proteoglycan (PG) demonstrates a prophylactic effect against collagen-induced arthritis (CIA) pathogenesis.
- PG attenuates CIA by modulating the immune response to collagen stimulation and reducing local inflammatory cytokine and chemokine production in the joints.
- These findings suggest PG as a potential therapeutic agent for managing rheumatoid arthritis (RA).
