Lipopolysaccharide accelerates collagen‐induced arthritis in association with rapid and continuous production of inflammatory mediators and anti‐type II collagen antibody

Collagen‐induced arthritis (CIA) is an animal model for rheumatoid arthritis (RA). Lipopolysaccharide (LPS) is known to accelerate CIA; however, the pathogenetic mechanisms are not yet fully understood. In this study, type II collagen (CII)‐immunized mice were found to have marked increases in degree of expression of mRNA of inflammatory mediators such as tumor necrosis factor alpha (TNF‐α), interleukin (IL)‐1β, and macrophage inflammatory protein‐2 (MIP‐2) in their arthritic paws and of serum anti‐CII antibody concentration before the onset of arthritis induced by LPS injection. The gene expression was rapid and continuous after direct activation of nuclear factor κB. The amounts of mRNA of TNF‐α, IL‐1β, and MIP‐2, as well as of matrix metalloproteinases and the receptor activator of nuclear factor κB ligand, increased with the development of arthritis, correlated positively with clinical severity and corresponded with histopathological changes. Moreover, anti‐TNF‐α neutralizing antibody inhibited the development of LPS‐accelerated CIA and a single injection of recombinant mouse TNF‐α induced increases in anti‐CII antibody concentrations, suggesting TNF‐α may contribute to the development of arthritis by both initiation of inflammation and production of autoantibodies. These data suggest that exacerbation of RA by LPS is associated with rapid and continuous production of inflammatory mediators and autoantibodies.     

Chemical Composition of Bawei Longzuan Granule and Its Anti‐Arthritic Activity on Collagen‐Induced Arthritis in Rats by Inhibiting Inflammatory Responses

Bawei Longzuan granule (BLG) is a representative Zhuang medicine preparation. The present work aims to characterize the chemical constituents of BLG and evaluate its anti‐arthritic activity. The major chemical constituents of BLG were tentatively identified by ultra‐performance liquid chromatography‐quadrupole time‐of‐flight mass spectrometry (UPLC‐Q‐TOF/MS), which revealed the presence of some alkaloids (e. g., magnoflorine, sinomenine and nitidine) and flavonoids (e. g., hesperidin, diosmin and sinensetin) that may be partly responsible for the anti‐arthritic effect of BLG. In addition, the collagen‐induced arthritis (CIA) model in rats was induced by intradermal injection of bovine collagen‐II in complete Freund's adjuvant at the base of tail. The CIA rats received oral administration of BLG (1.25, 2.5 and 5 g/kg) for 30 days. Then, various indicators were determined to evaluate its anti‐arthritic activity, including paw swelling, arthritic score, body weight, knee joint pathology, thymus index and spleen index. Additionally, the serum levels of tumor necrosis factor (TNF)‐α, interferon (IFN)‐γ, interleukin (IL)‐1β, IL‐6, IL‐4 and IL‐10 were measured to determine the underlying mechanisms. The results showed that BLG efficiently ameliorated the severity of arthritis in CIA rats by decreasing paw swelling and arthritis score and improving the histological lesions of knee joint. Moreover, the serum levels of several pro‐inflammatory cytokines (i. e., IL‐1β, TNF‐α, IL‐6 and IFN‐γ) were downregulated, whereas two anti‐inflammatory factors (i. e., IL‐4 and IL‐10) were upregulated after BLG administration. These results indicated that BLG possessed promising therapeutic effect on collagen‐induced arthritis by inhibiting inflammatory responses. BLG can be used as a complementary or alternative traditional medicine to treat rheumatoid arthritis.     

Aortic VCAM‐1: an early marker of vascular inflammation in collagen‐induced arthritis

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in rheumatoid arthritis (RA). There are limited experimental data on vascular involvement in arthritis models. To study the link between CVD and inflammation in RA, we developed a model of vascular dysfunction and articular inflammation by collagen‐induced arthritis (CIA) in C57Bl/6 (B6) mice. We studied the expression of vascular inflammatory markers in CIA with and without concomitant hyperlipidic diet (HD). Collagen‐induced arthritis was induced with intradermal injection of chicken type‐II collagen followed by a boost 21 days later. Mice with and without CIA were fed a standard diet or an HD for 12 weeks starting from the day of the boost. Arthritis severity was evaluated with a validated clinical score. Aortic mRNA levels of vascular cell adhesion molecule‐1 (VCAM‐1), inducible nitric oxide synthase (iNOS) and interleukin‐17 were analysed by quantitative RT‐PCR. Vascular cell adhesion molecule‐1 localization in the aortic sinus was determined by immunohistochemistry. Atherosclerotic plaque presence was assessed in aortas. Collagen‐induced arthritis was associated with increased expression of VCAM‐1, independent of diet. VCAM‐1 overexpression was detectable as early as 4 weeks after collagen immunization and persisted after 15 weeks. The HD induced atheroma plaque formation and aortic iNOS expression regardless of CIA. Concomitant CIA and HD had no additive effect on atheroma or VCAM‐1 or iNOS expression. CIA and an HD diet induced a distinct and independent expression of large‐vessel inflammation markers in B6 mice. This model may be relevant for the study of CVD in RA.     

miR‐124a inhibits the proliferation and inflammation in rheumatoid arthritis fibroblast‐like synoviocytes via targeting PIK3/NF‐κB pathway

Abnormal hyperplasia of fibroblast‐like synoviocytes (FLS) leads to the progression of rheumatoid arthritis (RA). This study aimed to investigate the role of miR‐124a in the pathogenesis of RA. The viability and cell cycle of FLS in rheumatoid arthritis (RAFLS) were evaluated by Cell Counting Kit 8 and flow cytometry assay. The expression of PIK3CA, Akt, and NF‐κB in RAFLS was examined by real‐time PCR and Western blot analysis. The production of tumour necrosis factor (TNF)‐α and interleukin (IL)‐6 was detected by ELISA. The joint swelling and inflammation in collagen‐induced arthritis (CIA) mice were examined by histological and immunohistochemical analysis. We found that miR‐124a suppressed the viability and proliferation of RAFLS and increased the percentage of cells in the G1 phase. miR‐124a suppressed PIK3CA 3'UTR luciferase reporter activity and decreased the expression of PIK3CA at mRNA and protein levels. Furthermore, miR‐124a inhibited the expression of the key components of the PIK3/Akt/NF‐κB signal pathway and inhibited the expression of pro‐inflammatory factors TNF‐α and IL‐6. Local overexpression of miR‐124a in the joints of CIA mice inhibited inflammation and promoted apoptosis in FLS by decreasing PIK3CA expression. In conclusion, miR‐124a inhibits the proliferation and inflammation in RAFLS via targeting PIK3/NF‐κB pathway. miR‐124a is a promising therapeutic target for RA.     

Rationally designed ligand‐independent peptide inhibitors of TREM‐1 ameliorate collagen‐induced arthritis

Triggering receptor expressed on myeloid cells 1 (TREM‐1) is critically involved in the pathogenesis of rheumatoid arthritis (RA). In contrast to cytokine blockers, therapeutic blockade of TREM‐1 can blunt excessive inflammation while preserving the capacity for microbial control. However, the nature of the TREM‐1 ligand(s) and mechanisms of TREM‐1 signalling are still not yet well understood, impeding the development of clinically relevant inhibitors of TREM‐1. The aim of this study was to evaluate the anti‐arthritic activity of a novel, ligand‐independent TREM‐1 inhibitory nonapeptide GF9 that was rationally designed using the signalling chain homo oligomerization (SCHOOL) model of cell signalling. Free GF9 and GF9 bound to macrophage‐targeted nanoparticles that mimic human high‐density lipoproteins (GF9‐HDL) were used to treat collagen‐induced arthritis (CIA). We also tested if 31‐mer peptides with sequences from GF9 and helices 4 (GE31) and 6 (GA31) of the major HDL protein, apolipoprotein A‐I, are able to perform three functions: assist in the self‐assembly of GA/E31‐HDL, target these particles to macrophages and block TREM‐1 signalling. We showed that GF9, but not control peptide, ameliorated CIA and protected against bone and cartilage damage. The therapeutic effect of GF9 was accompanied by a reduction in the plasma levels of macrophage colony‐stimulating factor and pro‐inflammatory cytokines such as tumour necrosis factor‐α, interleukin (IL)‐1 and IL‐6. Incorporation of GF9 alone or as a part of GE31 and GA31 peptides into HDL significantly increased its therapeutic efficacy. Collectively, our findings suggest that TREM‐1 inhibitory SCHOOL sequences may be promising alternatives for the treatment of RA.     

Suppression of collagen‐induced arthritis by oral administration of transgenic rice seeds expressing altered peptide ligands of type II collagen

Rheumatoid arthritis (RA) is an autoimmune disease associated with the recognition of self proteins secluded in arthritic joints. We previously reported that altered peptide ligands (APLs) of type II collagen (CII256‐271) suppress the development of collagen‐induced arthritis (CIA). In this study, we generated transgenic rice expressing CII256‐271 and APL6 contained in fusion proteins with the rice storage protein glutelin in the seed endosperm. These transgene products successfully and stably accumulated at high levels (7–24 mg/g seeds) in protein storage vacuoles (PB‐II) of mature seeds. We examined the efficacy of these transgenic rice seeds by performing oral administration of the seeds to CIA model mice that had been immunized with CII. Treatment with APL6 transgenic rice for 14 days significantly inhibited the development of arthritis (based on clinical score) and delayed disease onset during the early phase of arthritis. These effects were mediated by the induction of IL‐10 from CD4⁺ CD25^? T cells against CII antigen in splenocytes and inguinal lymph nodes (iLNs), and treatment of APL had no effect on the production of IFN‐γ, IL‐17, IL‐2 or Foxp3⁺ Treg cells. These findings suggest that abnormal immune suppressive mechanisms are involved in the therapeutic effect of rice‐based oral vaccine expressing high levels of APLs of type II collagen on the autoimmune disease CIA, suggesting that the seed‐based mucosal vaccine against CIA functions via a unique mechanism.     

The naturally occurring flavonoid nobiletin reverses methotrexate resistance via inhibition of P-glycoprotein synthesis

Methotrexate (MTX) is the first-line treatment for rheumatoid arthritis (RA). However, after long-term treatment, some patients develop resistance. P-glycoprotein (P-gp), as an indispensable drug transporter, is essential for mediating this MTX resistance. In addition, nobiletin (NOB), a naturally occurring polymethoxylated flavonoid, has also been shown to reverse P-gp–mediated MTX resistance in RA groups; however, the precise role of NOB in this process is still unclear. Here, we administered MTX and NOB alone or in combination to collagen II-induced arthritic (CIA) mice and evaluated disease severity using the arthritis index, synovial histopathological changes, immunohistochemistry, and P-gp expression. In addition, we used conventional RNA-seq to identify targets and possible pathways through which NOB reverses MTX-induced drug resistance. We found that NOB in combination with MTX could enhance its performance in synovial tissue and decrease P-gp expression in CIA mice compared to MTX treatment alone. In vitro, in MTX-resistant fibroblast-like synoviocytes from CIA cells (CIA-FLS/MTX), we show that NOB treatment downregulated the PI3K/AKT/HIF-1α pathway, thereby reducing the synthesis of the P-gp protein. In addition, NOB significantly inhibited glycolysis and metabolic activity of CIA-FLS/MTX cells, which could reduce the production of ATP and block P-gp, ultimately decreasing the efflux of MTX and maintaining its anti-RA effects. In conclusion, this study shows that NOB overcomes MTX resistance in CIA-FLS/MTX cells through the PI3K/AKT/HIF-1α pathway, simultaneously influencing metabolic processes and inhibiting P-gp–induced drug efflux.     

Revealing the Active Constituents and Mechanisms of Semiliquidambar cathayensis Chang Roots against Rheumatoid Arthritis through Network Pharmacology,Molecular Docking,and in Vivo Experiment

Semiliquidambar cathayensis Chang roots (SC) are traditional Chinese medicine for treating rheumatoid arthritis (RA). However, the effect and potential mechanism of SC remain unclear. This study aims to reveal the anti-RA constituents and mechanisms of SC based on network pharmacology, molecular docking, and adjuvant-induced arthritis (AIA) model rat experiment. In this work, 9 potential active constituents, including kaempferol, quercetin, naringenin, paeoniflorin, catechin, fraxin, gentianin, hesperetin, and ellagic acid 3,3′,4-trimethyl ether, in SC crossed 65 target genes of RA. In addition, 28 core targets were enriched in inflammation and others, among which interleukin-17 (IL-17) and tumor necrosis factor (TNF) were the major targets. The binding of bio-constituents with IL-17 and TNF were performed using molecular docking. Rat experiment demonstrated that the extract of SC restored body weight loss, reduced arthritis score and the indices of thymus and spleen, alleviated ankle joint histopathology, decreased the levels of rheumatoid factor (RF), C-reactive protein (CRP), IL-17, TNF-α, IL-1β, IL-6, cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX), and matrix metalloproteinase-2 (MMP-2), whereas elevated the levels of IL-4 and IL-10. Collectively, it was the first time to comprehensively reveal the anti-RA efficacy and mechanism of SC via suppressing the inflammatory pathway based on network pharmacology, molecular docking, and experimental verification, which provide chemical and pharmacological evidences for the clinical application of SC.     

Acacetin inhibits expression of matrix metalloproteinases via a MAPK‐dependent mechanism in fibroblast‐like synoviocytes

It is well known that rheumatoid arthritis (RA) is an autoimmune joint disease in which fibroblast‐like synoviocytes (FLSs) play a pivotal role. In this study, we investigated the anti‐arthritic properties of acacetin in FLSs. The expression of matrix metalloproteinase (MMP)‐1, MMP‐3 and MMP‐13 were investigated by quantitative RT‐PCR and western blot at gene and protein levels. At the same time, the phosphorylation of mitogen‐activated protein kinases (MAPK) was investigated. The DNA‐binding activity of NF‐κB was investigated by electrophoretic mobility shift assay. We found that acacetin inhibits p38 and JNK phosphorylation and reduces MMP‐1, MMP‐3 and MMP‐13 expression in interleukin‐1β‐induced FLSs. Our results suggest that acacetin has antiarthritic effects in FLSs. Thus, acacetin should be further studied for the treatment of arthritis.     

Anti‐Inflammatory Effect of Novel 7‐Substituted Coumarin Derivatives through Inhibition of NF‐κB Signaling Pathway

A series of novel 7‐substituted coumarin derivatives were synthesized and evaluated. Biological screening results obtained by the evaluation of the compounds’ inhibition against LPS‐induced IL‐6 and TNF‐α release in RAW 264.7 cells indicated that most compounds exhibited potent anti‐inflammatory activity. Among them, N‐(3‐methoxybenzyl)‐2‐[(2‐oxo‐2H‐chromen‐7‐yl)oxy]acetamide ( 2d ) showed the best activity. The potential targets of title compound 2d were reversely screened with the molecular modeling software, Discovery Studio 2017 R2. Screening and molecule docking results showed that 2d could bind to the active site (NLS Polypeptide) of NF‐κB p65, and this binding affinity was confirmed by surface plasmon resonance (SPR) analysis. Furthermore, Western blot assay showed that 2d remarkably blocked the NF‐κB signaling pathway in vitro. Collectively, all these findings suggested that compound 2d might be a promising lead compound worthy of further pursuit.     

A combined network pharmacology and molecular biology approach to investigate the active ingredients and potential mechanisms of mulberry (Morus alba L.) leaf on obesity

BackgroundAs one of traditional Chinese medicine, mulberry leaf is abundant in diverse active ingredients and widely used for the treatment of metabolic disease and its complications. However, there are a few of reports on its application in the prevention and treatment of obesity. And the molecular mechanism on the anti-obesity of mulberry leaf are unknown till now.PurposeThe present study aimed to evaluate the potential ingredients and targets of mulberry leaf and uncover the anti-obesity mechanisms by using the network pharmacology tactics and verify its effect by biological experiments.Study designActive ingredients and key targets of mulberry leaf, genes related to obesity were screened through public database. Based on the results of network pharmacology, the flavonoids-enriched fraction of mulberry leaf (MLF) was extracted and composition of this fraction was identified. After that, HepG2 cells model of lipid accumulation was established for verifying the effect of MLF and related mechanisms.ResultsA total of 37 active ingredients in mulberry leaf, 192 predicted biological targets and 8813 obesity-related targets were determined, of which 180 overlapping targets might have obvious curative effects on obesity. The networks showed that mulberry leaf might play a role through key targets, such as AKT, MAPK and IL-6, and regulated PI3K-Akt signaling pathway. Based on HPLC-ESI-QQQ-MS analysis, 13 constituents of MLF were identified, including 9 flavonoids. Furthermore, HepG2 cells model of lipid accumulation was established. The results indicated that MLF treatment could down-regulate the secretion of inflammatory cytokines, as well as clearly inhibited lipid droplets formation and alleviated TC, TG, HDL-C and LDL-C levels. Positive effect was observed on hypolipidemic efficacy due to the regulation of PI3K/Akt/Bcl-xl pathway, as indicated by the amelioration of PI3K, Akt and Bcl-xl gene and protein expression.ConclusionThis study firstly systematically disclose the multi-ingredients, multi-targets mechanisms of mulberry leaf on obesity by using network pharmacology approach, and validate in HepG2 cells that the protective effect of MLF against obesity involved both inflammation response and lipid metabolism involving PI3K/Akt/Bcl-xl signaling pathway. It provides indications for further mechanistic research of mulberry leaf and also for the development as a potential candidate for the therapy for obese patients.     

Exercise prevents the effects of experimental arthritis on the metabolism and function of immune cells

Active lymphocytes (LY) and macrophages (MΦ) are involved in the pathophysiology of rheumatoid arthritis (RA). Due to its anti‐inflammatory effect, physical exercise may be beneficial in RA by acting on the immune system (IS). Thus, female Wistar rats with type II collagen‐induced arthritis (CIA) were submitted to swimming training (6 weeks, 5 days/week, 60 min/day) and some biochemical and immune parameters, such as the metabolism of glucose and glutamine and function of LY and MΦ, were evaluated. In addition, plasma levels of some hormones and of interleukin‐2 (IL‐2) were also determined. Results demonstrate that CIA increased lymphocyte proliferation (1.9‐ and 1.7‐fold, respectively, in response to concanavalin A (ConA) and lipopolysaccharide (LPS)), as well as macrophage H₂O₂ production (1.6‐fold), in comparison to control. Exercise training prevented the activation of immune cells, induced by CIA, and established a pattern of substrate utilization similar to that described as normal for these cells. Exercise also promoted an elevation of plasma levels of corticosterone (22.2%), progesterone (1.7‐fold) and IL‐2 (2.6‐fold). Our data suggest that chronic exercise is able to counterbalance the effects of CIA on cells of the IS, reinforcing the proposal that the benefits of exercise may not be restricted to aerobic capacity and/or strength improvement. Copyright © 2010 John Wiley & Sons, Ltd.     

Sinomenine ameliorates arthritis via MMPs, TIMPs, and cytokines in rats

Rheumatoid arthritis (RA) is a chronic, inflammatory autoimmune disease that results in progressive joint destruction and substantial morbidity. The stem of the Chinese medicinal plant, Sinomenium acutum Rehder & Wilson (Family Menispermaceae), has been used to treat various rheumatic and arthritic diseases, of which the major bioactive component is sinomenine. We investigated the nature and molecular mechanisms of the anti-arthritic effect of sinomenine on collagen-induced arthritis in female Wistar rats. The results showed that sinomenine markedly suppressed the incidence and disease progression of established CIA, showing as dramatic reduction of paw swelling, ESR, and arthritic scores. Sinomenine suppressed the production of proinflammatory cytokines IL-1β and IL-6 in serum, inhibited the protein expressions and activities of MMP-2 and MMP-9, and elevated the protein expressions and activities of TIMP-1 and TIMP-3 in rat paw tissues.     

Virtual screening of active compounds from Artemisia argyi and potential targets against gastric ulcer based on Network pharmacology

Artemisia argyi (AA) is one of the renowned herbs in China often used in the treatment of gastric ulcer (GU). Aiming to predict the active compounds and systematically investigate the mechanisms of Artemisia argyi for GU treatment, the approach of network pharmacology, molecular docking, gene ontology (GO) analysis, and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis were adopted, respectively, in present study. A total of 13 predicted targets of the 103 compounds in Artemisia argyi were obtained. Sorted by pathogenic mechanisms of targets and structure types of compounds, it was revealed that flavonoids and sesquiterpenes had better performance than monoterpenes. The network analysis showed that Phospholipase a2 (PA21B), Sulfotransferase family cytosolic 2b member 1 (ST2B1), Nitric-oxide synthase, endothelial (NOS3), Gastrin (GAST), neutrophil collagenase (MMP-8), Leukotriene A-4 hydrolase (LKHA4), Urease maturation factor HypB (HYPB), and Periplasmic serine endoprotease DegP (HtrA) were the key targets with intensely interaction. The functional enrichment analysis indicated that AA probably produced the gastric mucosa protection effects by synergistically regulating many biological pathways, such as NF-κB signaling pathway, HIF-1 signaling pathway, TNF signaling pathway, VEGF signaling pathway, and Toll-like receptor signaling pathway, etc. In addition, C73 and C15 might be promising leading compounds with good molecular docking score. As a consequence, this study holistically illuminates the active constituents and mechanisms based on data analysis, which contributes to searching for leading compounds and the development of new drugs for gastric ulcer.     

Induction of Krüppel‐like factor 2 reduces K/BxN serum‐induced arthritis

Krüppel‐like factor 2 (KLF2) critically regulates activation and function of monocyte, which plays important pathogenic role in progressive joint destruction in rheumatoid arthritis (RA). It is yet to be established the molecular basis of KLF2‐mediated regulation of monocytes in RA pathogenesis. Herein, we show that a class of compound, HDAC inhibitors (HDACi) induced KLF2 expression in monocytes both in vitro and in vivo. KLF2 level was also elevated in tissues, such as bone marrow, spleen and thymus in mice after infusion of HDACi. Importantly, HDACi significantly reduced osteoclastic differentiation of monocytes with the up‐regulation of KLF2 and concomitant down‐regulation of matrixmetalloproteinases both in the expression level as well as in the protein level. In addition, HDACi reduced K/BxN serum‐induced arthritic inflammation and joint destruction in mice in a dose‐dependent manner. Finally, co‐immunoprecipitation and overexpression studies confirmed that KLF2 directly interacts with HDAC4 molecule in cells. These findings provide mechanistic evidence of KLF2‐mediated regulation of K/BxN serum‐induced arthritic inflammation.     

Retinoic acid attenuates rheumatoid inflammation in mice

Retinoic acid is the active vitamin A derivative and is well-known to have diverse immunomodulatory actions. In this study, we investigated the impact of all-trans retinoic acid (ATRA), a biologic key metabolite of vitamin A, on the development of arthritis and the pathophysiologic mechanisms by which ATRA might have antiarthritic effects in animal model of rheumatoid arthritis (RA; collagen-induced arthritis [CIA] in DBA/1J mice). We showed that treatment with ATRA markedly suppressed the clinical and histologic signs of arthritis in the CIA mice. It reduced the expression of IL-17 in the arthritic joints. Interestingly, Foxp3(+) regulatory T cells were markedly increased and IL-17-producing CD4(+) T cells (Th17 cells) were decreased in the spleens of ATRA-treated mice. In vitro treatment with ATRA induced the expression of Foxp3 and repressed the IL-17 expression in the CD4(+) T cells in mice. ATRA suppressed the production of total IgG and IgG2a in splenocytes that were stimulated by LPS. It also reduced serum levels of total IgG and IgG2 anti-collagen Abs and germinal center formation in CIA mice. In addition, the ATRA-treated mice showed decreased osteoclast formation in arthritic joints. Moreover, ATRA downregulated the expression of receptor activator of NF-κB ligand, the leading player of osteoclastogenesis, in the CD4(+) T cells and fibroblast-like synoviocytes from patients with RA. Furthermore, ATRA prevented both human monocytes and mice bone marrow-derived monocytes/macrophage cells from differentiating into osteoclasts. These data suggest ATRA might be an effective treatment modality for RA patients.     

Analysis of marker compounds with anti‐platelet aggregation effects in mailuoning injection using platelet binding assay combined with HPLC‐DAD‐ESI‐MS and solid‐phase extraction technique

Introduction – Mailuoning is prepared from a traditional formula of Chinese medicines and widely used as an antithrombotic agent. In this study, the platelet binding assay was used as a novel biospecific separation and analysis method to explore its active constituents, which could be considered as marker compounds for quality control. Objective – To establish a rapid and simple method to predict marker compounds in herbal medicine injection and evaluate the effects of those compounds. Material and methods – Platelets were used to bind and separate constituents. Binding constituents were analysed and taken as potential active compounds for further evaluation. Solid‐phase‐extraction was adopted to improve sensitivity. HPLC‐DAD and ESI‐MS were used to determine the binding constituents. Results – Five compounds were extracted through the platelet binding process and identified as neochlorogenic acid, caffeic acid, isochlorogenic acid and their isomers. Caffeic acid was selected for the flow cytometric assay to test its effect on platelets activation, which was determined by CD62P (P‐selectin) expression. The results indicated that caffeic acid could significantly inhibit platelet activation while chlorogenic acid did not. Conclusion – Caffeic acid could be considered as a marker compound of Mailuoning injection due to its anti‐platelet effect. The study also suggested that platelet binding assay combined with some preconcentration technique could be efficiently used to predict anti‐platelet compounds in complicated herbal medicines. Copyright © 2010 John Wiley & Sons, Ltd.     

Revealing synergistic mechanism of multiple components in Stauntonia brachyanthera Hand.-Mazz. for gout by virtual screening and system pharmacological approach

Stauntonia brachyanthera Hand.-Mazz. (SB), reported as a traditional Chinese medicine, displays a wide spectrum of interesting bioactivities, such as anti-inflammatory and analgesia. It is noteworthy that anti-gout effects of the components in SB have been reported. Hence, this study contributes to the prediction of promising active compounds and mechanisms for the treatment of gout. The active compounds with better oral bioavailability, and drug-likeness of SB were selected for further investigation by the approach of network pharmacology, molecular docking, gene ontology (GO) analysis, and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis, respectively. A total of 34 predicted targets and 98 compounds in SB were obtained. Sorted by structure types of compounds, phenylethanoid glycosides exhibited the best anti-gout activity, followed by phenolics and flavonoids. What’s more, it was shown in the network analysis that Serine/threonine-protein kinase mTOR (mTOR), Mitogen-activated protein kinase 12 (MAPK12), tumor necrosis factor (TNF-α), Integrin alpha-4 (ITGA4) and Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit gamma (PIK3CG) were the key targets with intensely interaction, which should be attached more attention for further study. The functional enrichment analysis indicated that SB probably produced the anti-gout effects by synergistically regulating many biological pathways, such as MAPK signaling pathway, PI3K-Akt signaling pathway, Toll-like receptor signaling pathway and NOD-like receptor signaling pathway, etc. In addition, C61, C67, C68 and C81 might be promising leading compounds with good molecular docking score. As a consequence, the active constituents and mechanisms based on data analysis were holistically illuminated, which was of vital importance to the development of new drugs for gout.