Dataset Information

Effect of Angiotensin II on Bone Erosion and Systemic Bone Loss in Mice with Tumor Necrosis Factor-Mediated Arthritis.

ABSTRACT: Angiotensin II (Ang II) is the main effector peptide of the renin-angiotensin system (RAS), which regulates the cardiovascular system. The RAS is reportedly also involved in bone metabolism. The upregulation of RAS components has been shown in arthritic synovial tissues, suggesting the potential involvement of Ang II in arthritis. Accordingly, in the present study, we investigated the role of Ang II in bone erosion and systemic bone loss in arthritis. Ang II was infused by osmotic pumps in tumor necrosis factor-transgenic (TNFtg) mice. Ang II infusion did not significantly affect the severity of clinical and histological inflammation, whereas bone erosion in the inflamed joints was significantly augmented. Ang II administration did not affect the bone mass of the tibia or vertebra. To suppress endogenous Ang II, Ang II type 1 receptor (AT1R)-deficient mice were crossed with TNFtg mice. Genetic deletion of AT1R did not significantly affect inflammation, bone erosion, or systemic bone loss. These results suggest that excessive systemic activation of the RAS can be a risk factor for progressive joint destruction. Our findings indicate an important implication for the pathogenesis of inflammatory bone destruction and for the clinical use of RAS inhibitors in patients with rheumatoid arthritis.

SUBMITTER: Akagi T

PROVIDER: S-EPMC7312645 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Effect of Angiotensin II on Bone Erosion and Systemic Bone Loss in Mice with Tumor Necrosis Factor-Mediated Arthritis.

Akagi Takahiko T Mukai Tomoyuki T Mito Takafumi T Kawahara Kyoko K Tsuji Shoko S Fujita Shunichi S Uchida Haruhito A HA Morita Yoshitaka Y

International journal of molecular sciences 20200610 11

Angiotensin II (Ang II) is the main effector peptide of the renin-angiotensin system (RAS), which regulates the cardiovascular system. The RAS is reportedly also involved in bone metabolism. The upregulation of RAS components has been shown in arthritic synovial tissues, suggesting the potential involvement of Ang II in arthritis. Accordingly, in the present study, we investigated the role of Ang II in bone erosion and systemic bone loss in arthritis. Ang II was infused by osmotic pumps in tumor ...[more]

PMID: 32532031

Similar Datasets

Project description:BackgroundThe types of bone damage in rheumatoid arthritis (RA) include joint erosion, periarticular osteoporosis, and systemic osteoporosis. Janus kinase (JAK) inhibitors ameliorate inflammation and joint erosion in RA, but their effect on the three types of bone loss have not been reportedly explored in depth. We aimed to clarify how JAK inhibitors influence the various types of bone loss in arthritis by modulating osteoclastic bone resorption and/or osteoblastic bone formation.MethodsCollagen-induced arthritis (CIA) mice were treated with a JAK inhibitor after the onset of arthritis. Micro-computed tomography (μCT) and histological analyses (bone morphometric analyses) on the erosive calcaneocuboid joint, periarticular bone (distal femur or proximal tibia), and vertebrae were performed. The effect of four different JAK inhibitors on osteoclastogenesis under various conditions was examined in vitro.ResultsThe JAK inhibitor ameliorated joint erosion, periarticular osteopenia and systemic bone loss. It reduced the osteoclast number in all the three types of bone damage. The JAK inhibitor enhanced osteoblastic bone formation in the calcaneus distal to inflammatory synovium in the calcaneocuboid joints, periarticular region of the tibia and vertebrae, but not the inflamed calcaneocuboid joint. All the JAK inhibitors suppressed osteoclastogenesis in vitro to a similar extent in the presence of osteoblastic cells. Most of the JAK inhibitors abrogated the suppressive effect of Th1 cells on osteoclastogenesis by inhibiting IFN-γ signaling in osteoclast precursor cells, while a JAK inhibitor did not affect this effect due to less ability to inhibit IFN-γ signaling.ConclusionsThe JAK inhibitor suppressed joint erosion mainly by inhibiting osteoclastogenesis, while it ameliorated periarticular osteopenia and systemic bone loss by both inhibiting osteoclastogenesis and promoting osteoblastogenesis. These results indicate that the effect of JAK inhibitors on osteoclastogenesis and osteoblastogenesis depends on the bone damage type and the affected bone area. In vitro studies suggest that while JAK inhibitors inhibit osteoclastic bone resorption, their effects on osteoclastogenesis in inflammatory environments vary depending on the cytokine milieu, JAK selectivity and cytokine signaling specificity. The findings reported here should contribute to the strategic use of antirheumatic drugs against structural damages in RA.

Project description:To define the pathogenesis of bone marrow (BM) involvement in systemic lupus erythematosus (SLE).Tumor necrosis factor ? (TNF?) levels, cell death, and cellular damage in BM from SLE patients, controls, and mice with pristane-induced lupus were analyzed using a morphometric technique and immunohistochemistry. The pathogenesis of BM abnormalities was studied in wild-type (WT), TNF?(-/-) , Toll-like receptor-deficient (TLR-7(-/-) ), interferon (IFN)-?/?/? receptor-knockout (IFNAR(-/-) ), and B cell-deficient (?mt) mice treated with pristane. Flow cytometry was used to examine TNF? production (by intracellular staining) and plasma cell/plasmablast development. CXCL12 expression was determined by quantitative polymerase chain reaction.BM from SLE patients exhibited striking death of niche and hematopoietic cells associated with TNF? overproduction. BM from mice with a type I IFN-mediated lupus syndrome induced by pristane showed similar abnormalities. TNF? was produced mainly by BM neutrophils, many with phagocytosed nuclear material (lupus erythematosus cells). TNF? production was abolished in pristane-treated TLR-7(-/-) and ?mt mice but was restored in ?mt mice by infusing normal plasma. Pristane-treated WT and IFNAR(-/-) mice developed anemia, BM hypocellularity, and extramedullary hematopoiesis, which were absent in TLR-7(-/-) and TNF?(-/-) mice. Additionally, the expression of CXCL12, which is produced by stromal cells and mediates homing of hematopoietic cells and plasmablasts, was decreased in BM from pristane-treated WT mice but was normal in BM from pristane-treated TNF?(-/-) mice.Although autoantibodies and glomerulonephritis are type I IFN dependent, lupus-associated BM abnormalities were TLR-7 and TNF? driven but type I IFN independent, suggesting that lupus is a disorder of innate immunity in which TLR-7 activation by phagocytosed nuclei causes relentless type I IFN and TNF? production mediating glomerulonephritis and hematologic involvement, respectively.

Dataset Information

Effect of Angiotensin II on Bone Erosion and Systemic Bone Loss in Mice with Tumor Necrosis Factor-Mediated Arthritis.

Publications

Effect of Angiotensin II on Bone Erosion and Systemic Bone Loss in Mice with Tumor Necrosis Factor-Mediated Arthritis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets