naphthoquinones and Arthritis--Rheumatoid

Inflammation plays a significant role in the pathogenesis of chronic diseases. Inflammatory diseases such as bacterial diseases, Alzheimer's disease, rheumatoid arthritis, multiple sclerosis, and so on, impose huge costs on the health systems. On the other hand, some side effects have been reported for the classic drugs used to treat these diseases. Plants phytochemicals have revealed important prospects in the handling and controlling of human diseases. β-lapachone, is a derivative of the naturally occurring element lapachol, from Tabebuia avellanedae and its anti-inflammatory effects have been reported in several reports. This review summarized the evidence from cell and animal studies supporting the anti-inflammatory role of β-lapachone and discussed its potential mechanisms.

Topics: Alzheimer Disease; Animals; Anti-Inflammatory Agents; Arthritis, Rheumatoid; Bacterial Infections; Humans; Inflammation; Multiple Sclerosis; Naphthoquinones; Tabebuia

This study aimed to explore the effects of plumbagin on rheumatoid arthritis (RA) and its mechanism. The RA cell model was simulated following the treatment of interleukin-1β (IL-1β). After the treatment of various concentrations of plumbagin, the impact of plumbagin on the cell viability was examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The collagen-induced arthritis (CIA) model was established using the solution of bovine type II collagen. Hematoxylin-eosin staining was used to observe the changes of ankle joint tissue, while enzyme-linked immunosorbent assay and western blot were applied to detect the level of inflammatory cytokines. Plumbagin inhibited the viability of human fibroblast-like synoviocytes (HFLS) at the concentration of 1 ~ 3.5 μM. The inhibitory effect of 1 μM plumbagin on cell proliferation was similar to that of methotrexate, the drug used as the positive control. Plumbagin downregulated the levels of inflammatory cytokines and matrix metalloproteinases (MMPs) in IL-1β-treated HFLS, and suppressed the activation of IκB and nuclear factor kappa-B (NF-κB) as well as the entry of p65 into the nucleus. It was also demonstrated in animal experiments that plumbagin inhibited the activation of NF-κB pathway, down-regulated the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and MMPs, and alleviated joint damage in CIA-modeled mice. Collectively speaking, plumbagin might down-regulate the levels of inflammatory cytokines and MMPs through inhibiting the activation of the NF-κB pathway, thereby attenuating RA-induced damage to cells and joints.

Topics: Animals; Arthritis, Experimental; Arthritis, Rheumatoid; Cattle; Cells, Cultured; Cytokines; Interleukin-1beta; Interleukin-6; Matrix Metalloproteinases; Mice; Naphthoquinones; NF-kappa B; Synovial Membrane; Tumor Necrosis Factor-alpha

Shikonin is the main component of the traditional Chinese medicine comfrey, which can inhibit the activity of PKM2 by regulating glycolysis and ATP production. Rheumatoid arthritis synovial cells (RA-FLSs) have been reported to increase glycolytic activity and have other similar hallmarks of metabolic activity. In this study, we investigated the effects of shikonin on glycolysis, mitochondrial function, and cell death in RA-FLSs. The results showed that shikonin induced apoptosis and autophagy in RA-FLSs by activating the production of reactive oxygen species (ROS) and inhibiting intracellular ATP levels, glycolysis-related proteins, and the PI3K-AKT-mTOR signaling pathway. Shikonin can significantly reduce the expression of apoptosis-related proteins, paw swelling in rat arthritic tissues, and the levels of inflammatory factors in peripheral blood, such as TNF-α, IL-6, IL-8, IL-10, IL-17A, and IL-1β while showing less toxicity to the liver and kidney.

Topics: Adenosine Triphosphate; Animals; Anti-Inflammatory Agents; Apoptosis; Arthritis, Rheumatoid; Autophagy; Cell Line; Disease Models, Animal; Energy Metabolism; Humans; Interleukins; Male; Naphthoquinones; Phosphatidylinositol 3-Kinase; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Signal Transduction; Synoviocytes; TOR Serine-Threonine Kinases

Zicao is the dried root of Lithospermum erythrorhizon Sieb, et Zucc, Arnebia euchroma (Royle) Johnst, or Arnebia guttata Bunge and commonly used to treat viral infection, inflammation, arthritis and cancer in China.Shikonin (SKN) is a major active chemical component isolated from zicao. Previous research showed that SKN has anti-inflammatory, immunomodulatory and analgesic effects, and inhibits the development of arthritis and the condition of collagen arthritis (CIA) mice; nevertheless, its role in the angiogenesis of rheumatoid arthritis (RA) has not been elucidated.. The purpose of this study was to investigate the antiangiogenic activity of SKN in CIA rats and various angiogenesis models.. The anti-arthritic effect of SKN on CIA rats was tested by arthritis score, arthritis incidence, radiological observation and histopathology evaluation of inflamed joints. Vessel density evaluated with CD31 immunohistochemistry/immunofluorescence in joint synovial membrane tissues of CIA rats, chick chorioallantoic membrane assay, rat aortic ring assay, and the migration, invasion, adhesion and tube formation of human umbilical vein endothelial (HUVEC) cells induced by tumor necrosis factor (TNF)-α were used to measured the antiangiogenenic activity of SKN. Moreover, the effect of SKN on the expression of angiogenic mediators, such as vascular endothelial growth factor (VEGF), VEGFR2, TNF-α, interleukin (IL)-1β, platelet derived growth factor (PDGF) and transforming growth factor (TGF)-β in sera and joint synovia of rats, and in TNF-α-induced MH7A/HUVEC cells were measured by immunohistochemistry, enzyme linked immunosorbent assay, Western blot and/or real-time polymerase chain reaction (PCR). Through the analysis of protein and mRNA levels of phosphoinositide 3-kinase (PI3K), Akt and PTEN, and the autophosphorylation of ERK1/2, JNK and p38 in joint synovia of rats and in TNF-α-induced HUVEC cells, the molecular mechanism of its inhibition was elucidated by using Western blot and/or real-time PCR.. These findings indicate for the first time that SKN has the anti-angiogenic effect in RA in vivo, ex vivo and in vitro by interrupting the PI3K/AKT and MAPKs signaling pathways.

Topics: Angiogenesis Inhibitors; Animals; Anti-Inflammatory Agents, Non-Steroidal; Arthritis, Experimental; Arthritis, Rheumatoid; Chick Embryo; Chorioallantoic Membrane; Human Umbilical Vein Endothelial Cells; Humans; Inflammation; Male; MAP Kinase Signaling System; Naphthoquinones; Neovascularization, Pathologic; Phosphatidylinositol 3-Kinase; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley

Recent studies indicate that glucose metabolism is altered in rheumatoid arthritis. We hypothesize that Pkm2, as a key regulatory enzyme of glycolysis pathway, triggers the activation of macrophages (Mφ), which results in proinflammatory cytokine production during the arthritis progress. In this study, Pkm2 was found to be overexpressed in ED1-positive Mφ in spleens and synovial tissues from arthritic rats via immunofluorescence, Western blotting, and quantitative RT-PCR. To reveal the role of Pkm2, Dark Agouti rats were treated with either Pkm2 enzyme inhibitor shikonin or the RNA interference plasmids of Pkm2 and negative control plasmids, respectively, via i.p. injection. Pkm2 intervention could alleviate the severity of pristane-induced arthritis in aspects of the macroscopic arthritis score, perimeter changes of midpaw, and the synovitis and destruction of the bone and cartilage as well as reduce the ED1 and p-Stat1-positive cell population in rat synovial tissues. Silencing Pkm2 by RNA interference in classical activated rat and mouse Mφ resulted in less Tnf-α, Il-1β production via Stat1 signaling. Collectively, Pkm2 is highly expressed in ED1-positive Mφ of spleens and synovial tissues from arthritic rats and promotes Mφ activation via Stat1 signaling. Pkm2 might be a promising selective metabolic target molecule for rheumatoid arthritis treatment.

Topics: Animals; Arthritis, Experimental; Arthritis, Rheumatoid; Gene Knockdown Techniques; Humans; Macrophages; Mice; Naphthoquinones; Pyruvate Kinase; Rats; RAW 264.7 Cells; RNA, Small Interfering; Severity of Illness Index; Signal Transduction; STAT1 Transcription Factor; Synovial Membrane

To observe the effect of shikonin on the proliferation, migration, adhesion and invasion of rheumatoid arthritis(RA) fibroblast like synoviocytes induced by tumor necrosis factor-α(TNF-α), and to explore its mechanism of action from aspects of protein kinase B(Akt) and mitogen activated protein kinase(MAPK) signaling pathways. TNF-α(20 ng·mL~(-1)) was used in this experiment to induce human RA fibroblast like synovial cell line(MH7 A). After addition of different concentrations of shikonin(0.025, 0.05, 0.1 pmol·L~(-1)), the proliferation, migration, adhesion and invasion ability of MH7 A cells were detected by MTT test, scratch test, adhesion test, Transwell invasion test, respectively. Protein expression of Akt and MAPK signaling pathway molecules in MH7 A cells was detected by Western blot. The results showed that as compared with the control group, TNF-α could significantly induce the proliferation, migration, adhesion and invasion of MH7 A cells, and increase the phosphorylation level of Akt, JNK, p38 and extracellular regulatory protein kinase(ERK). As compared with the TNF-α group, shikonin had no significant effect on TNF-α-induced proliferation of MH7 A cells after 24 h treatment, and it could reduce the TNF-α-induced proliferation of MH7 A cells in a concentration dependent manner after 48 h treatment. Shikonin also significantly reduced the TNF-α-induced migration, adhesion, invasion and phosphorylation levels of Akt, JNK, p38, ERK in MH7 A cells within 24 h. These results suggested that shikonin could reduce the proliferation, migration, adhesion and invasion ability of MH7 A cells induced by TNF-α, and its mechanism may be related to the down-regulation of Akt and MAPK signaling pathway activation.

Topics: Arthritis, Rheumatoid; Cell Movement; Cell Proliferation; Cells, Cultured; Fibroblasts; Humans; Naphthoquinones; Synovial Membrane; Synoviocytes; Tumor Necrosis Factor-alpha

Shikonin, a major effective component in the Chinese herbal medicine Lithospermum erythrorhizon Sieb., exhibits an anti-inflammatory property towards rheumatoid arthritis (RA), but the potential mechanism is unclear. Our aim was to investigate the mechanism of shikonin on the lipopolysaccharide (LPS)-induced fibroblast-like synoviocyte (LiFLS) inflammation model. Fibroblast-like synoviocytes (FLSs) were treated with 200 μg/ml of LPS for 24 h to establish the RA-like model, LiFLS. FLSs were pretreated with shikonin (0.1-1 μM) for 30 min in the treatment groups. Quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assays were used to detect mRNA and protein levels of interleukin (IL)-10 and tumor necrosis factor (TNF)-α. Signal proteins involved in IL-10 production were analyzed by Western blotting. Shikonin significantly reversed the inhibitory effects of LPS on IL-10 expression in FLSs by inactivating the PKC-NF-κB pathway. In addition, shikonin inhibited LPS-induced TNF-α expression in FLSs, and this effect was markedly diminished by IL-10-neutralizing antibody. The IL-10-mediated suppression of TNF-α transcription was demonstrated by no response to the protein synthesis inhibitor cyclohexamide and no mRNA decay. Shikonin inhibits LPS-induced TNF-α production in FLSs through suppressing the PKC-NF-κB-dependent decrease in IL-10, and this study also highlights the potential application of shikonin in the treatment of RA.

Topics: Arthritis, Rheumatoid; Drugs, Chinese Herbal; Humans; Interleukin-10; Naphthoquinones; NF-kappa B; Tumor Necrosis Factor-alpha

The inhibition of pyrimidine biosynthesis by blocking the dihydroorotate dehydrogenase (DHODH) activity, the prime target of leflunomide (LEF), has been proven to be an effective strategy for rheumatoid arthritis (RA) treatment. However, a considerable proportion of RA patients are refractory to LEF. Here, we investigated lapachol (LAP), a natural naphthoquinone, as a potential DHODH inhibitor and addressed its immunosuppressive properties.. Molecular flexible docking studies and bioactivity assays were performed to determine the ability of LAP to interact and inhibit DHODH. In vitro studies were conducted to assess the antiproliferative effect of LAP using isolated lymphocytes. Finally, collagen-induced arthritis (CIA) and antigen-induced arthritis (AIA) models were employed to address the anti-arthritic effects of LAP.. We found that LAP is a potent DHODH inhibitor which had a remarkable ability to inhibit both human and murine lymphocyte proliferation in vitro. Importantly, uridine supplementation abrogated the antiproliferative effect of LAP, supporting that the pyrimidine metabolic pathway is the target of LAP. In vivo, LAP treatment markedly reduced CIA and AIA progression as evidenced by the reduction in clinical score, articular tissue damage, and inflammation.. Our findings propose a binding model of interaction and support the ability of LAP to inhibit DHODH, decreasing lymphocyte proliferation and attenuating the severity of experimental autoimmune arthritis. Therefore, LAP could be considered as a potential immunosuppressive lead candidate with potential therapeutic implications for RA.

Topics: Animals; Arthritis, Experimental; Arthritis, Rheumatoid; CD4-Positive T-Lymphocytes; Cell Proliferation; Dihydroorotate Dehydrogenase; Humans; Immunosuppressive Agents; Lymphocyte Activation; Male; Mice; Mice, Inbred C57BL; Mice, Inbred DBA; Molecular Docking Simulation; Naphthoquinones; Oxidoreductases Acting on CH-CH Group Donors; Rats; Rats, Wistar

Although various drugs for the treatment of rheumatoid arthritis (RA) have been used in clinics, RA is not completely curable to date. Thus, to seek new drugs for the treatment of RA has been a hotspot. Hydroxynaphthoquinones are the major anti-inflammatory active constituents in Arnebia euchroma (Royle) Johnst. The present study aims to evaluate the anti-arthritic activity of a hydroxynaphthoquinone mixture (HM) of A. euchroma (Royle) Johnst, including its anti-inflammatory and analgesic effects. The anti-arthritic efficacy of HM was examined using complete Freund's adjuvant- and bovine type II collagen-induced arthritic models. The paw edema, polyarthritis index and histopathological change were evaluated. The analgesic effect was assessed using the chemical and thermal models of nociception. Results found that HM administered prophylactically and curatively showed marked anti-arthritic activity by suppressing the paw swelling and development of inflammation, lowering the levels of TNF-α and IL-1β and protecting cartilage and bone from damage. The protection of HM was superior to that of reference drugs such as prednisone acetate or etanercept, and showed no direct deleterious effect. Similarly, HM showed significant analgesic effects. In summary, HM possessed potent anti-arthritic activity. It could relieve inflammatory symptoms and protect against joint destruction. These findings indicate that HM would be a potential therapeutic agent for arthritic disease, which provide pharmacological evidence for its clinical application.

Topics: Analgesics; Animals; Anti-Inflammatory Agents; Antirheumatic Agents; Arthritis, Experimental; Arthritis, Rheumatoid; Bone Diseases; Boraginaceae; Cartilage Diseases; Cattle; Collagen Type II; Edema; Etanercept; Freund's Adjuvant; Hot Temperature; Immunoglobulin G; Inflammation; Interleukin-1beta; Joint Diseases; Male; Naphthoquinones; Phytotherapy; Plant Extracts; Prednisone; Rats; Rats, Sprague-Dawley; Receptors, Tumor Necrosis Factor; Tumor Necrosis Factor-alpha

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation in joints and subsequent destruction of cartilage and bone. Inflammatory mediators such as PGs and proinflammatory cytokines contribute to RA progress. Pin1, a peptidyl prolyl isomerase, plays important pathophysiological roles in several diseases, including cancer and neurodegeneration. We found that both Pin1 and cyclooxygenase-2 (COX-2) were highly expressed in ankle tissues of type II collagen-induced RA mice. HTB-94 cells overexpressing Pin1 and primary cultured human chondrocytes showed increased basal expression of proinflammatory proteins (COX-2, inducible NO synthase, TNF-alpha, and IL-1beta). Site-directed mutagenesis revealed that Pin1-mediated transcriptional activation of COX-2 was coordinately regulated by NF-kappaB, CREB, and C/EBP. Gel shift, reporter gene, and Western blot analyses confirmed that NF-kappaB, CREB, and C/EBP were consistently activated in chondrocytes overexpressing Pin1. Treatment of RA mice with juglone, a chemical inhibitor of Pin1, significantly reduced RA progress and COX-2 expression in the ankle tissues. Moreover, juglone dose dependently decreased the basal COX-2 expression in primary cultured chondrocytes from RA patients. These results demonstrate that Pin1 induction during RA progress stimulates proinflammatory protein expression by activating NF-kappaB, CREB, and C/EBP, and suggest that Pin1 is a potential therapeutic target of RA.

Topics: Animals; Ankle Joint; Arthritis, Rheumatoid; Cell Line; Cells, Cultured; Chondrocytes; Collagen Type II; Cyclic AMP Response Element-Binding Protein; Cyclooxygenase 2; Genes, Reporter; Humans; Interleukin-1beta; Mice; Naphthoquinones; NF-kappa B; NIMA-Interacting Peptidylprolyl Isomerase; Nitric Oxide Synthase Type II; Peptidylprolyl Isomerase; Steroid Isomerases; Transfection; Tumor Necrosis Factor-alpha

The pathophysiology of rheumatoid arthritis (RA) includes inflammation, synoviocyte proliferation, angiogenesis, and matrix metalloproteinase-driven degradation processes. The objective of this study was to investigate a variety of structurally unrelated anticancer topoisomerase inhibiting agents as inhibitors of aspects of these disease processes involved in RA.. The topoisomerase I inhibitors camptothecin and beta-laperchone and the topoisomerase II inhibitors, etoposide, doxorubicin, plumbagin and menadione were used in this study. Crystal induced neutrophil activation was measured by luminol dependent chemiluminescence. Synoviocyte proliferation was measured by an MTT assay using HIG 82 rabbit synoviocytes in cell culture. Angiogenesis was measured using the chorioallantoic membrane of the chick embryo. Chondrocyte (culture primary cells) expression of the matrix metalloproteinases collagenase and stromelysin was measured by Northern Blot analysis.. All agents inhibited synoviocyte proliferation to some degree. Camptothecin had no effect on neutrophil activation but inhibited all other processes at low (nanomolar) concentrations. Plumbagin and menadione inhibited neutrophil activation, collagenases expression and angiogenesis. The other agents had little effect on neutrophil activation (except beta-laperchone) but inhibited angiogenesis and collagenase expression to a lesser degree than camptothecin.. These studies support the explorative use of topoisomerase I (particularly camptothecin) and II inhibitors as potential agents for use against RA.

Topics: Animals; Antirheumatic Agents; Arthritis, Rheumatoid; Camptothecin; Cattle; Cell Proliferation; Cells, Cultured; Chick Embryo; Chondrocytes; Doxorubicin; Enzyme Inhibitors; Etoposide; Interleukin-1; Naphthoquinones; Neutrophils; Rabbits; Synovial Membrane; Topoisomerase I Inhibitors; Topoisomerase II Inhibitors; Vitamin K 3