Eun-Gyeong Lee

Quercetin Inhibits IL-1β-Induced Proliferation and Production of MMPs, COX-2, and PGE2 by Rheumatoid Synovial Fibroblast

This study was aimed to determine the effects of quercetin on the interleukin-1β (IL-1β)-induced proliferation of rheumatoid synovial fibroblasts (RASFs) and production of matrix metalloproteinases (MMPs), cyclooxygenase (COX), and prostaglandin E2 (PGE2) by RASFs. The proliferation and apoptosis of RASFs was evaluated with CCK-8 reagent and flow cytometry in the presence of IL-1with CCK-8 reagquercetin. The expression of MMPs, IL-1β enhanced the expression of MMP-1, MMP-3, tissue inhibitor of metalloproteinase (TIMP)-1, COXs, PGE2, and intracellular mitogen-activated protein kinase (MAPK) signalings including phosphorylated extracellular signal-regulated kinase (p-ERK), p-p38, phosphorylated c-Jun N-terminal kinase (p-JNK), and nuclear factor kB (NF-kB) were examined by immunoblotting or semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) in conditions as described above. Quercetin inhibits unstimulated and IL-1β-induced proliferation of RASFs and MMP-1, 3, COX-2 messenger ribonucleic acid and protein expression, PGE2 production induced with IL-1β. Quercetin also inhibits the phosphorylation of ERK-1/2, p38, JNK and activation of NF-kB by IL-1ed. These results indicate that quercetin inhibits synovial fibroblasts proliferation and MMPs, COX-2, and PGE2 production, which involved joint destruction in rheumatoid arthritis (RA), and suggest that it might be a new therapeutic agent for management of RA.

Kaempferol inhibits IL-1β-stimulated, RANKL-mediated osteoclastogenesis via downregulation of MAPKs, c-Fos, and NFATc1.

Kaempferol is one of the most common flavonoid that is present in a variety of vegetables and fruits and has effects on bone metabolism. The present study was performed to define the effects of kaempferol on interleukin (IL)-1β-stimulated receptor activator of NF-κB ligand (RANKL)-mediated osteoclast differentiation. Bone marrow cells were harvested from 6-week-old male imprinting control region mice, and the differentiation of osteoclasts from these cells was evaluated by tartrate-resistant acid phosphatase staining and resorption pit formation assay. Phosphorylated extracellular signal-regulated kinase (p-ERK), phosphorylated p38, phosphorylated c-Jun amino-terminal kinase, NF-κB (p65), IκBα, c-Fos, and nuclear factor of activated T cells c1 (NFATc1) expressions were examined by Western blotting and quantitative RT-PCR. Kaempferol inhibits IL-1β-stimulated, RANKL-mediated osteoclast differentiation and also inhibits IL-1β-stimulated, RANKL-mediated phosphorylation of ERK 1/2, p38 and JNK MAP kinases, and expressions of c-Fos and NFATc1. These results indicate that kaempferol has an inhibitory role in the bone loss by preventing osteoclast formation and suggest that it might be a novel therapeutic agent for the treatment of inflammatory arthritis by managing bone destruction.

A pathogenic role for ER stress-induced autophagy and ER chaperone GRP78/BiP in T lymphocyte systemic lupus erythematosus

Abnormal regulation of ER stress and apoptosis has been implicated in autoimmune disorders. Particularly, ER stress‐induced autophagy and the role of GRP78, or BiP in T lymphocyte survival and death in SLE are poorly understood. This study investigated the pathogenic roles of ER stress‐induced autophagy and GRP78/BiP in apoptosis of T lymphocytes. We compared spontaneous and induced autophagy and apoptosis of T lymphocytes in healthy donors and patients with SLE. The molecular mechanism of altered autophagy and apoptosis was investigated in T lymphocytes transfected with siRNA for beclin 1 and CHOP and T lymphocytes overexpressing GRP78. Decreased autophagy and increased apoptosis in response to TG‐induced ER stress were observed in lupus T lymphocytes. GRP78 and ER stress‐signaling molecules, such as PERK, p‐eIF2α, IRE1, and ATF6 decreased, whereas CHOP levels increased in lupus T cells in response to TG. The levels antiapoptotic molecules, Bcl‐2 and Bcl‐XL decreased, whereas the proapoptotic molecules, Bax and caspase 6, increased in lupus T cells. The TG‐induced ER stress altered autophagy and apoptosis, which in turn, led to abnormal T cell homeostasis with increased apoptotic T cell death. We hypothesize that aberrant autophagy of T lymphocytes as a result of ER stress and decreased GRP78 expression is involved in the pathogenesis of SLE and might serve as important therapeutic targets.

Ethyl acetate fraction from Angelica sinensis inhibits IL-1β-induced rheumatoid synovial fibroblast proliferation and COX-2, PGE2, and MMPs production

BackgroundThe root of Angelica sinensis (AS), also known as “Dang-gui,” was a popular herbal medicine widely used in the treatment of gynecological diseases in China, Korea, and Japan for a long time. This study aimed to determine the effects of ethyl acetate fraction from Angelica sinensis (EAAS) on the interleukin-1β (IL-1β)-induced proliferation of rheumatoid arthritis synovial fibroblasts (RASFs), and production of matrix metalloproteinases (MMPs), cyclooxygenase (COX) 2, and prostaglandin E2 (PGE2), involved in articular bone and cartilage destruction, by RASFs.ResultsRASF proliferation was evaluated with cholecystokinin octapeptide (CCK-8) reagent in the presence of IL-1β with/without EAAS. Expression of MMPs, tissue inhibitor of metalloproteinases-1 (TIMP-1), COXs, PGE2, and intracellular mitogen-activated protein kinase (MAPK) signaling molecules, including p-ERK, p-p38, p-JNK, and NF-κB, were examined using immunoblotting or semi-quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. EAAS inhibited IL-1β-induced RASF proliferation; MMP-1, MMP-3, and COX-2 mRNA and protein expressions; and PGE2 production. EAAS also inhibits the phosphorylation of ERK-1/2, p38, and JNK, and activation of NF-κB by IL-1β.ConclusionEAAS might be a new therapeutic modality for rheumatoid arthritis management.

Ethyl acetate fraction from Cudrania tricuspidata inhibts IL-1β-induced rheumatoid synovial fibroblast proliferation and MMPs, COX-2 and PGE2 production

OBJECTIVES The objective of this study is to determine the effects of Ethyl acetate fraction from Cudrania tricuspidata (EACT) on the interleukin-1b (IL-1b)-induced proliferation of rheumatoid synovial fibroblasts (RASFs) and production of matrix metalloproteinases (MMPs), cyclooxygenase (COX) and prostaglandin E2 (PGE2) by RASFs. MATERIALS AND METHODS The proliferation of RASFs was evaluated with CCK-8 reagent in the presence of IL-1b with/without EACT. The expression of MMPs, TIMP-1, COXs, PGE2 and intracellular MAPK signalings, including p-ERK, p-p38, p-JNK and NF-kB were examined by immunoblotting or semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and ELISA in conditions as described above. RESULTS EACT inhibits IL-1β-induced proliferation of RASFs and MMP-1, 3, COX-2 mRNA and protein expression, PGE2 production induced with IL-1b. EACT also inhibits the phosphorylation of ERK-1/2, p38, JNK and activation of NF-kB by IL-1b. CONCLUSIONS These results suggest that EACT might be involved in synovial fibroblast proliferation and MMPs, COX-2, and PGE2 production, which are involved in joint destruction in rheumatoid arthritis (RA), indicating that this might be a new therapeutic modality for management of rheumatoid arthritis.

Sulforaphane Inhibits IL-1β-Induced Proliferation of Rheumatoid Arthritis Synovial Fibroblasts and the Production of MMPs, COX-2, and PGE2

This study was performed to define the effects of sulforaphane on interleukin-1β (IL-1β)-induced proliferation of rheumatoid arthritis synovial fibroblasts (RASFs), the expression of matrix metalloproteinases (MMPs) and cyclooxygenase (COX), and the production of prostaglandin E2 (PGE2) by RASFs. The proliferation of RASFs was evaluated with CCK-8 reagent in the presence of IL-1β with/without sulforaphane. The expression of MMPs, tissue inhibitor of metalloproteinase-1, COXs, intracellular mitogen-activated protein kinase signalings, including p-ERK, p-p38, p-JNK, and nuclear factor-kappaB (NF-kB), and the production of PGE2 were examined by Western blotting or semi-quantitative RT-PCR and ELISA. Sulforaphane inhibits unstimulated and IL-1β-induced proliferation of RASFs; the expression of MMP-1, MMP-3, and COX-2 mRNA and protein; and the PGE2 production induced by IL-1β. Sulforaphane also inhibits the phosphorylation of ERK-1/2, p-38, and JNK and activation of NF-kB by IL-1β. These results indicate that sulforaphane inhibits the proliferation of synovial fibroblasts, the expression of MMPs and COX-2, and the production of PGE2, which are involved in synovitis and destruction of RA, and suggest that sulforaphane might be a new therapeutic agent for RA.

Ethyl Acetate Fraction from Cudrania Tricuspidata Inhibits IL-1β-Stimulated Osteoclast Differentiation through Downregulation of MAPKs, c-Fos and NFATc1

Background/Aims The present study was performed to determine the effects of the ethyl acetate extract of Cudrania tricuspidata (EACT) on interleukin (IL)-1β-stimulated receptor activator of NF-κB ligand (RANKL)-mediated osteoclast differentiation. Methods Bone marrow cells were harvested from 6-week-old male imprinting control region mice, and the differentiation of osteoclasts from these cells was evaluated by tartrate-resistant acid phosphatase and resorption pit formation assay. Phosphorylated extracellular signal regulated kinase (p-ERK), phosphorylated p38, phosphorylated c-Jun amino-terminal kinase, NF-κB (p65), IκBα, c-Fos, and nuclear factor of activated T-cells c1 (NFATc1) expression was examined by immunoblotting and quantitative reverse transcription-polymerase chain reaction. Results EACT inhibits IL-1β-stimulated RANKL-mediated osteoclast differentiation. EACT also inhibits IL-1β-stimulated RANKL-mediated phosphorylation of ERK 1/2, p38 mitogen activated protein kinase, and expression of c-Fos and NFATc1. Conclusions These results suggest that EACT may be involved in the inhibition of bone loss by preventing osteoclast formation and may be used to manage bone destruction in inflammatory diseases, such as rheumatoid arthritis.

Adrenomedullin Inhibits IL-1β-Induced Rheumatoid Synovial Fibroblast Proliferation and MMPs, COX-2 and PGE2 Production

To determine the effects of adrenomedullin (AM) on interleukin (IL)-1β-induced proliferation of rheumatoid synovial fibroblasts (RASFs) and production of matrix metalloproteinases (MMPs), cyclooxygenase (COX) and prostaglandin E2 (PGE2) by RASFs. The RASFs proliferation was evaluated with CCK-8 reagent in the presence of IL-1β with/without AM (1-52) and AM inhibitor (AM (22-52)). MMPs, tissue inhibitor of metalloproteinase (TIMP-1), COXs, PGE2 and intracellular mitogen-activated protein kinase (MAPK) signalings, including p-ERK, p-p38, p-JNK were examined by immunoblotting or semiquantitative RT-PCR and ELISA. AM (1-52) inhibited IL-1β-induced RASFs proliferation and inhibited MMP-1, 3, COX-2 and PGE2 production. AM (1-52) also inhibited IL-1β-induced phosphorylation of ERK-1/2, p38, JNK. AM 22-52 inhibited the effects of AM (1-52) on proliferation of RASFs and production of MMP-1, 3, COX-2 via MAPKs. These results suggest that AM might involved joint destruction in rheumatoid arthritis and indicate that it might be a new therapeutic modality for management of this disease.

Adrenomedullin inhibits MAPK pathway-dependent rheumatoid synovial fibroblast-mediated osteoclastogenesis by IL-1 and TNF-α

The objective of this study is to determine the effects of adrenomedullin (AM) on IL-1- and TNF-α-induced rheumatoid synovial fibroblasts (RASFs)-mediated osteoclastogenesis. The formation of osteoclasts in co-cultures of RASFs and peripheral blood mononuclear cells was evaluated by tartrate-resistant acid phosphatase and resorption pit formation assay. The expression of RANKL, OPG, p-ERK, p-p38, and p-JNK was examined by immunoblotting and quantitative reverse transcription-polymerase chain reaction. AM (1-52) inhibits IL-1- and TNF-α-induced RASFs-mediated osteoclastogenesis. AM affected IL-1-, TNF-α-induced RANKL and OPG expression in RASFs. AM also inhibits IL-1 and TNF-α-induced phosphorylation of ERK-1/2, p38 MAPK, and JNK. Inhibitor of AM (AM 22-52) inhibits the effects of AM on the osteoclastogenesis. These results suggest that AM might be involved in the inflammatory cytokines-mediated osteoclastogenesis and thus bone damage, and indicate that it can be a new therapeutic strategy against joint destruction in RA.

Increased RANKL-mediated osteoclastogenesis by interleukin-1β and endoplasmic reticulum stress.

OBJECTIVE The mechanism by which IL-1β and thapsigargin (TG)-induced endoplasmic reticulum (ER) stress modulate the receptor activator of nuclear factor kappa-B ligand (RANKL)-mediated osteoclastogenesis remains elusive. Thus, we investigated the osteoclast-specific and ER signals in osteoclastogenesis of bone marrow-derived cells. METHODS Bone marrow cells (BMCs) were obtained from 5-week-old male ICR mice and cultured to be differentiated into osteoclasts with M-CSF and RANKL in the presence or absence of IL-1β, TG, or 4-phenylbutyric acid (PBA), an ER stress-reducing drug. The formation of osteoclasts was evaluated by tartrate-resistant acid phosphatase (TRAP) staining and resorption pit assay with a dentine slice. The molecular mechanism of IL-1β and ER stress in osteoclastogenesis was investigated in BMCs transfected with siRNA for GRP78, PERK and IRE1 using reverse transcription-polymerase chain reaction and immunoblotting for osteoclast-specific and ER stress signaling molecules. RESULTS IL-1β and ER stress induced by TG-augmented the formation of osteoclasts, which was significantly inhibited by PBA and was mediated with osteoclast-specific signals, including c-Fos, NFATc1, and ER stress- associated signaling pathways, such as PERK, IRE1, GRP78, and eIF2α. siRNA-mediated knockdown of ER stress signals inhibited the expression of NFATc1 and c-Fos, thus reducing IL-1β and/or TG-induced formation of osteoclasts. CONCLUSIONS Osteoclastogenesis by IL-1β and/or ER stress is mainly associated with upregulation of eIF2α, GRP78, PERK and IRE1. These results suggest that the signaling pathway of ER stress-induced osteoclast formation might be a new therapeutic target to prevent inflammatory and destructive arthritic disease such as RA and diverse osteoporosis.