Transcription factors

Tanshinones and diethyl blechnics with anti-inflammatory and anti-cancer activities from Salvia miltiorrhiza Bunge (Danshen)

Four novel compounds (1-4) as well as fourteen reported compounds (5-18) were isolated and purified from Salvia miltiorrhiza Bunge (Danshen). The structures of novel compounds were determined by 1D and 2D NMR, HRESIMS data, etc. The anti-inflammatory properties of all the compounds on RAW264.7 macrophages and their cytotoxicity on H1299 and Bel-7402 cell lines coupled with a structure-activity relationship (SAR) were investigated. Compound 4 demonstrated the best anti-inflammatory activity and was chosen for further research. Compound 4 greatly suppressed secretion of nitric oxide (NO), tumor necrosis factor (TNF)-α and interleukin-6 (IL-6) in the RAW264.7 macrophages stimulated by LPS. Additionally, the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was decreased and the nuclear translocation of NF-κB was attenuated after treatment with compound 4 in vitro. Compound 4 was able to dramatically inhibit LPS-induced activation of JNK1/2 and ERK1/2 and remarkably disrupted the TLR4 dimerization in LPS-induced RAW264.7 macrophages. Thus, the new compound 4 suppressed LPS-induced inflammation partially is due to the blocking TLR4 dimerization. In addition, the anti-cancer activity investigation indicated that most of isolated compounds exhibited cytotoxicity and the SAR analysis showed that the intact D ring was indispensable and unsaturated D ring played vital role.

Norisoboldine alleviates joint destruction in rats with adjuvant-induced arthritis by reducing RANKL, IL-6, PGE(2), and MMP-13 expression

AIM

To explore the effects of norisoboldine (NOR), a major isoquinoline alkaloid in Radix Linderae, on joint destruction in rats with adjuvant-induced arthritis (AIA) and its underlying mechanisms.

METHODS

AIA was induced in adult male SD rats by intradermal injection of Mycobacterium butyricum in Freund's complete adjuvant at the base of the right hind paw and tail. From d 14 after immunization, the rats were orally given NOR (7.5, 15, or 30 mg/kg) or dexamethasone (0.5 mg/kg) daily for 10 consecutive days. Joint destruction was evaluated with radiological scanning and H&E staining. Fibroblast-like synoviocytes (FLS) were prepared from fresh synovial tissues in the AIA rats. The expression of related proteins and mRNAs were detected by ELISA, Western blotting and RT-PCR.

RESULTS

In AIA rats, NOR (15 and 30 mg/kg) significantly decreased the swelling of paws and arthritis index scores, and elevated the mean body weight. NOR (30 mg/kg) prevented both the infiltration of inflammatory cells and destruction of bone and cartilage in joints. However, NOR (15 mg/kg) only suppressed the destruction of bone and cartilage, but did not obviously ameliorate synovial inflammation. NOR (15 and 30 mg/kg) significantly decreased the serum levels of receptor activator of nuclear factor κB ligand (RANKL), IL-6, PGE2, and MMP-13, but not the osteoprotegerin and MMP-1 levels. The mRNA levels of RANKL, IL-6, COX-2, and MMP-13 in synovium were also suppressed. Dexamethasone produced similar effects in AIA rats as NOR did, but without elevating the mean body weight. In the cultured FLS, treatment with NOR (10 and 30 mmol/L) significantly decreased the secretion of RANKL, IL-6, PGE2, and MMP-13 proteins. Furthermore, the treatment selectively prevented the activation of MAPKs, AKT and transcription factor AP-1 component c-Jun, but not the recruitment of TRAF6 or the activation of JAK2/STAT3. Treatment of the cultured FLS with the specific inhibitors of p38, ERK, AKT, and AP-1 significantly decreased the secretion of RANKL, IL-6, PGE2, and MMP-13 proteins.

CONCLUSION

NOR can alleviate joint destruction in AIA rats by reducing RANKL, IL-6, PGE2, and MMP-13 expression via the p38/ERK/AKT/AP-1 pathway.

A synthetic hydroxypropenone inhibits nitric oxide, prostaglandin E2, and proinflammatory cytokine synthesis

HMP [3-(2-hydroxyphenyl)-1-(5-methyl-furan-2-y-l) propenone] was evaluated for its ability to inhibit the synthesis of major proinflammatory mediators and cytokines in interferon-gamma (IFN-gamma)- and lipopolysaccharide (LPS)-induced RAW 264.7 cells and phorbol myristate acetate (PMA)-differentiated/LPS-induced U937 cells. HMP suppressed the production of nitric oxide (NO) with significant inhibitory effects at doses as low as 0.78 microM (P < 0.05). Prostaglandin E2 (PGE2) secretion was also inhibited at doses of 12.5 microM and above (P < 0.01). The secretion of both TNF-alpha and IL-6 were only inhibited at the highest dose used (25 microM; P < 0.001). IL-1beta secretion was also inhibited from 12.5 microM onwards (P < 0.01). This inhibition was demonstrated to be caused by down-regulation of inducible enzymes, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), without direct effect upon iNOS or COX-2 enzyme activity. HMP only inhibited iNOS (P < 0.001) and IL-1beta (P < 0.05) gene expression at the highest tested concentration. HMP did not affect the secretion of chemokines IL-8 and monocyte chemotactic protein-1 (MCP-1) and the anti-inflammatory cytokine IL-10. The most striking effect of HMP was its NO inhibitory activity and therefore we conclude that HMP is a selective inhibitor of iNOS.

Shikonin reduces oedema induced by phorbol ester by interfering with IkappaBalpha degradation thus inhibiting translocation of NF-kappaB to the nucleus

BACKGROUND AND PURPOSE

In the present paper we studied the effect of shikonin on ear oedema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), and determined the mechanisms through which shikonin might exert its topical anti-inflammatory action.

EXPERIMENTAL APPROACH

Acute ear oedema was induced in mice by topical application of TPA. The in vitro assays used macrophages RAW 264.7 cells stimulated with lipopolysaccharide. Cyclooxygenase-2, inducible nitric oxide synthase, protein kinase Calpha, extracellular signal-regulated protein kinase (ERK), phosphorylated ERK (pERK), c-Jun N-terminal kinase (JNK), pJNK, p38, p-p38, p65, p-p65, inhibitor protein of nuclear factor-kappaB (NF-kappaB) (IkappaBalpha) and pIkappaBalpha were measured by Western blotting, activation and binding of NF-kappaB to DNA was detected by reporter gene and electrophoretic mobility shift assay, respectively, and NF-kappaB p65 localization was detected by immunocytochemistry.

KEY RESULTS

Shikonin reduced the oedema (inhibitory dose 50 = 1.0 mg per ear), the expression of cyclooxygenase-2 (70%) and of inducible nitric oxide synthase (100%) in vivo. It significantly decreased TPA-induced translocation of protein kinase Calpha, the phosphorylation and activation of ERK, the nuclear translocation of NF-kappaB and the TPA-induced NF-kappaB-DNA-binding activity in mouse skin. Moreover, in RAW 264.7 cells, shikonin significantly inhibited the binding of NF-kappaB to DNA in a dose-dependent manner and the nuclear translocation of p65.

CONCLUSIONS AND IMPLICATIONS

Shikonin exerted its topical anti-inflammatory action by interfering with the degradation of IkappaBalpha, thus inhibiting the activation of NF-kappaB.

Adapted Boolean network models for extracellular matrix formation

BACKGROUND

Due to the rapid data accumulation on pathogenesis and progression of chronic inflammation, there is an increasing demand for approaches to analyse the underlying regulatory networks. For example, rheumatoid arthritis (RA) is a chronic inflammatory disease, characterised by joint destruction and perpetuated by activated synovial fibroblasts (SFB). These abnormally express and/or secrete pro-inflammatory cytokines, collagens causing joint fibrosis, or tissue-degrading enzymes resulting in destruction of the extra-cellular matrix (ECM).We applied three methods to analyse ECM regulation: data discretisation to filter out noise and to reduce complexity, Boolean network construction to implement logic relationships, and formal concept analysis (FCA) for the formation of minimal, but complete rule sets from the data.

RESULTS

First, we extracted literature information to develop an interaction network containing 18 genes representing ECM formation and destruction. Subsequently, we constructed an asynchronous Boolean network with biologically plausible time intervals for mRNA and protein production, secretion, and inactivation. Experimental gene expression data was obtained from SFB stimulated by TGFbeta1 or by TNFalpha and discretised thereafter. The Boolean functions of the initial network were improved iteratively by the comparison of the simulation runs to the experimental data and by exploitation of expert knowledge. This resulted in adapted networks for both cytokine stimulation conditions. The simulations were further analysed by the attribute exploration algorithm of FCA, integrating the observed time series in a fine-tuned and automated manner. The resulting temporal rules yielded new contributions to controversially discussed aspects of fibroblast biology (e.g., considerable expression of TNF and MMP9 by fibroblasts stimulation) and corroborated previously known facts (e.g., co-expression of collagens and MMPs after TNFalpha stimulation), but also revealed some discrepancies to literature knowledge (e.g., MMP1 expression in the absence of FOS).

CONCLUSION

The newly developed method successfully and iteratively integrated expert knowledge at different steps, resulting in a promising solution for the in-depth understanding of regulatory pathways in disease dynamics. The knowledge base containing all the temporal rules may be queried to predict the functional consequences of observed or hypothetical gene expression disturbances. Furthermore, new hypotheses about gene relations were derived which await further experimental validation.

Gene expression profile of bladder tissue of patients with ulcerative interstitial cystitis

Background

Interstitial cystitis (IC), a chronic bladder disease with an increasing incidence, is diagnosed using subjective symptoms in combination with cystoscopic and histological evidence. By cystoscopic examination, IC can be classified into an ulcerative and a non-ulcerative subtype. To better understand this debilitating disease on a molecular level, a comparative gene expression profile of bladder biopsies from patients with ulcerative IC and control patients has been performed.

Results

Gene expression profiles from bladder biopsies of five patients with ulcerative IC and six control patients were generated using Affymetrix GeneChip expression arrays (Affymetrix – GeneChip^® Human Genome U133 Plus 2.0). More than 31,000 of > 54,000 tested probe sets were present (detection p-value < 0.05). The difference between the two groups was significant for over 3,500 signals (t-test p-value < 0.01), and approximately 2,000 of the signals (corresponding to approximately 1,000 genes) showed an IC-to-healthy expression ratio greater than two. The IC pattern had similarities to patterns from immune system, lymphatic, and autoimmune diseases. The dominant biological processes were the immune and inflammatory responses. Many of the up-regulated genes were expressed in leukocytes, suggesting that leukocyte invasion into the bladder wall is a dominant feature of ulcerative IC. Histopathological data supported these findings.

Conclusion

GeneChip expression arrays present a global picture of ulcerative IC and provide us with a series of marker genes characteristic for this subtype of the disease. Evaluation of biopsies from other bladder patients with similar symptoms (e.g. patients with non-ulcerative IC) will further indicate whether the data presented here will be valuable for the diagnosis of IC.

[Concepts on the pathogenesis of juvenile idiopathic arthritis]

There are various explanations for the development of juvenile idiopathic arthritis (JIA).Gene changes in the immune system can predispose to JIA and regulation of the immune system is crucial in the pathogenesis. The adaptive, acquired immune system probably plays a central role. Thus, in the case of JIA a conspicuous population of highly activated T-cells can be found in the synovia. B-cells are also involved, as indicated by positive ANA titers in JIA patients. Regulatory T-cells (Tregs) attempt to prevent the expansion of autoreactive T-cells.However, the natural or the innate immune system also plays a role. Thus a disorder of the inflammasome could underlie the cause of JIA with systemic onset. The interaction between congenital and adaptive immune system shows that a distinct spatial and temporal separation between the two immune systems is becoming increasingly difficult. An infection- and virus-related immune reaction could also be the cause of JIA. Proinflammatory cytokines are of proven significance in pathogenesis in terms of how they are released under stress, for example. New genomic and proteomic techniques are able to produce individualized profiles for each patient and allow for increasingly fine separation between subtypes, thus improving therapeutic possibilities.

Cells of the synovium in rheumatoid arthritis. Macrophages

The multitude and abundance of macrophage-derived mediators in rheumatoid arthritis and their paracrine/autocrine effects identify macrophages as local and systemic amplifiers of disease. Although uncovering the etiology of rheumatoid arthritis remains the ultimate means to silence the pathogenetic process, efforts in understanding how activated macrophages influence disease have led to optimization strategies to selectively target macrophages by agents tailored to specific features of macrophage activation. This approach has two advantages: (a) striking the cell population that mediates/amplifies most of the irreversible tissue destruction and (b) sparing other cells that have no (or only marginal) effects on joint damage.

NF-kappaB as a potential therapeutic target in osteoarthritis and rheumatoid arthritis

The family of nuclear factor-kappaB (NF-kappaB) transcription factors is intimately involved in the regulation of expression of numerous genes in the setting of the inflammatory response. Since inflammatory processes play a fundamental role in the damage of articular tissues, many in vitro and in vivo studies have examined the contribution of components of the NF-kappaB signaling pathways to the pathogenesis of various rheumatic diseases, in particular, of osteoarthritis (OA) and rheumatoid arthritis (RA). Inflammation, cartilage degradation, cell proliferation, angiogenesis and pannus formation are processes in which the role of NF-kappaB is prominent. Consequently, large efforts have been devoted to the study of the pharmacologic modulation of the NF-kappaB pathways. These studies have employed currently available therapeutic agents including non-steroidal anti-inflammatory drugs, corticosteroids, nutraceuticals and disease-modifying anti-rheumatic drugs, as well as novel small molecule inhibitors targeted to specific proteins of the NF-kappaB pathways. In addition, promising strategies such as improved antisense DNA therapy and RNA interference have been examined with encouraging results. However, since NF-kappaB also plays a crucial beneficial role in normal physiology and technical problems for effective gene therapy still remain, further research will be needed before NF-kappaB-aimed strategies become an effective therapy for joint diseases, such as OA and RA.

Glycoprotein isolated from Solanum nigrum L. inhibits the DNA-binding activities of NF-κB and AP-1, and increases the production of nitric oxide in TPA-stimulated MCF-7 cells

Solanum nigrum L. (SNL) has been used in traditional folk medicine to treat numerous cancers. We isolated a glycoprotein (150 kDa) from SNL and tested its effect on the modulation of transcriptional factors (NF-kappa B and AP-1) and iNO production in TPA induced-MCF-7 cells, which are part of the human breast cancer cell line, without estrogen receptors. However, the mechanism of SNL glycoprotein in pharmacological and biochemical actions in cancer cells has not been studied. To test the effect of SNL glycoprotein on the DNA-binding activities of nuclear factor-kappa B (NF-kappaB) and activator protein-1 (AP-1), and nitric oxide (NO) production, these experiments were carried out using electrophoretic mobility shift assays (EMSA), western blot analysis, and the Griess method. Results in this experiment showed that SNL glycoprotein inhibits 12-O-Tetra decanoylphorbol-13-acetate (TPA; 100 nM)-induced DNA-binding activities of NF-kappaB and AP-1, and enhances NO production in MCF-7 cells. That is, our results indicated that SNL glycoprotein has the capacity to modulate the TPA-induced DNA-binding activities of transcription factors and NO production, which play a critical role with respect to cytotoxicity in MCF-7 cells. Therefore, SNL glycoprotein might be one of the agents that blocks TPA-mediated signal responses in tumor cells.

Pharmacogenetics and personalised medicine

The traditional concern of pharmacogenetics was Mendelian (monogenic) variation, which visibly affected some drug responses. Pharmacogenetics was broadened by the observation that multifactorial genetic influences, in conjunction with environmental factors, usually determine drug responses. Variability of gene expression, a new theme of the science of genetics, also affects pharmacogenetics; for example, enhanced enzyme activity does not necessarily indicate a mutation, but may be the consequence of a drug-induced enhancement of gene expression. Methodological advances permit the conversion of pharmacogenetics into the broad practice of pharmacogenomics; this improves the possibility of identifying genetic causes of common diseases, which means establishing new drug targets, thereby stimulating the search for new drugs. While the main medical effect of pharmacogenetics was an improvement of drug safety, pharmacogenomics is hoped to improve drug efficacy. On the way to personalized medicine, we may stepwise improve the chances of choosing the right drug for a patient by categorizing patients into genetically definable classes that have similar drug effects (as, for example, human races, or any population group carrying a particular set of genes). It is wise to expect that, even after we have reached the goal to establish personalized medicine, we will not have eliminated all uncertainties.