New approaches to the treatment of inflammatory disease : focus on small-molecule inhibitors of signal transduction pathways

Ultra-Long-Term Anti-Inflammatory Polyphenol Capsule to Remodel the Microenvironment for Accelerating Osteoarthritis Healing by Single Dosage

Osteoarthritis (OA) is a common chronic inflammatory disease that leads to disability and death. Existing therapeutic agents often require frequent use, which can lead to drug resistance and long-term side effects. Polyphenols have anti-inflammatory and antioxidant potential. However, they are limited by their short half-life and low bioavailability. This work presents a novel pure polyphenol capsule for sustained release of polyphenols, which is self-assembled via hydrophobic and hydrogen bonds. The capsule enhances cellular uptake, scavenges reactive oxygen and nitrogen species, reduces inflammatory markers, and remodels the OA microenvironment by inhibiting the p38 MAPK pathway. The capsule overcomes the limitations of short half-life and low bioavailability of polyphenols and achieves single-dose cure in mouse and dog OA models, providing an optimal therapeutic window for OA repair. Taking advantage of simple manufacturing, convenient administration, and pure polyphenol composition, these capsules show great potential for clinical treatment of osteoarthritis and chronic inflammatory diseases.

Macrophage migration inhibitor factor (MIF): Potential role in cognitive impairment disorders

Macrophage migration inhibitory factor (MIF) is a cytokine in the immune system, participated in both innate and adaptive immune responses. Except from immune cells, MIF is also secreted by a variety of non-immune cells, including hematopoietic cells, endothelial cells (ECs), and neurons. MIF plays a crucial role in various diseases, such as sepsis, rheumatoid arthritis, acute kidney injury, and neurodegenerative diseases. The role of MIF in the neuropathogenesis of cognitive impairment disorders is emphasized, as it recruits multiple inflammatory mediators, leading to activating microglia or astrocyte-derived neuroinflammation. Furthermore, it contributes to the cell death of neurons and ECs with the binding of apoptosis-inducing factor (AIF) through parthanatos-associated apoptosis-inducing factor nuclease (PAAN) / MIF pathway. This review comprehensively delves into the relationship between MIF and the neuropathogenesis of cognitive impairment disorders, providing a series of emerging MIF-targeted pharmaceuticals as potential treatments for cognitive impairment disorders.

PIM kinase inhibitors: an updated patent review (2016-present)

INTRODUCTION

PIM Kinases (PIM-1, PIM-2, and PIM-3) have been reported to play crucial role in signaling cascades that govern cell survival, proliferation, and differentiation. Over-expression of these kinases leads to hematological malignancies such as diffuse large B cell lymphomas (DLBCL), multiple myeloma, leukemia, lymphoma and prostate cancer etc. PIM kinases as biomarkers and potential therapeutic targets have shown promise toward precision cancer therapy. The selective PIM-1, PIM-2, and/or PIM-3 isoform inhibitors have shown significant results in patients with advanced stages of cancer including relapsed/refractory cancer.

AREAS COVERED

A comprehensive literature review of PIM Kinases (PIM-1, PIM-2, and PIM-3) in oncogenesis, the patented PIM kinase inhibitors (2016-Present), and their pharmacological and structural insights have been highlighted.

EXPERT OPINION

Recently, PIM kinases viz. PIM-1, PIM-2, and PIM-3 (members of the serine/threonine protein kinase family) as therapeutic targets have attracted considerable interest in oncology especially in hematological malignancies. The patented PIM kinase inhibitors comprised of heterocyclic (fused)ring structure(s) like indole, pyridine, pyrazine, pyrazole, pyridazine, piperazine, thiazole, oxadiazole, quinoline, triazolo-pyridine, pyrazolo-pyridine, imidazo-pyridazine, oxadiazole-thione, pyrazolo-pyrimidine, triazolo-pyridazine, imidazo-pyridazine, pyrazolo-quinazoline and pyrazolo-pyridine etc. showed promising results in cancer chemotherapy.

Green Extracts with Metal-based Nanoparticles for Treating Inflammatory Diseases: A Review

Globally, high death rates and poor quality of life are caused mainly by inflammatory diseases. Corticosteroids, which may have systemic side effects and would enhance the risk of infection, are the common forms of therapy. The field of nanomedicine has created composite nanoparticles that carry a pharmacological carrier and target ligands for distribution to sites of inflammation with less systemic toxicity. However, their relatively large size often causes systemic clearance. An interesting approach is metal-based nanoparticles that naturally reduce inflammation. They are made not only to be small enough to pass through biological barriers but also to allow label-free monitoring of their interactions with cells. The following literature review discusses the mechanistic analysis of the anti-inflammatory properties of several metal-based nanoparticles, including gold, silver, titanium dioxide, selenium, and zinc oxide. Current research focuses on the mechanisms by which nanoparticles infiltrate cells and the anti-inflammatory techniques using herbal extracts-based nanoparticles. Additionally, it provides a brief overview of the literature on many environmentally friendly sources employed in nanoparticle production and the mechanisms of action of various nanoparticles.

Anti-Inflammatory and Anti-Oxidant Effects of Korean Ginseng Berry Extract in LPS-Activated RAW264.7 Macrophages

Inflammatory macrophages stimulated by LPS disrupt homeostasis in the production of inflammatory cytokines and nitric oxide (NO). These are the causes of inflammation-related diseases and various cancers. The present study aimed to evaluate the protective effects of Korean ginseng berry extract (KGB) on lipopolysaccharide (LPS)-induced inflammation in RAW264.7 macrophage cells. NO and prostaglandin E2 (PGE[Formula: see text] production was elevated in response to LPS stimulation and was dose-dependently reduced by pretreatment with KGB. The expression levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNA and protein were also reduced by KGB treatment. KGB treatment significantly suppressed the LPS-induced gene expression and production of cytokines, including interleukin (IL)-1[Formula: see text], IL-6, and tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]. Furthermore, KGB inhibited the translocation of nuclear expression of nuclear factor-kappa B (NF-[Formula: see text]B) by preventing inhibitory factor-kappa B (I[Formula: see text]B[Formula: see text] phosphorylation and suppressing the phosphorylation of extracellular signal-related kinase (ERK1/2), c-Jun N-terminal kinase (JNK), and p38. Additionally, decreased reactive oxygen species (ROS) generation and increased glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities were observed following KGB treatment. Taken together, these results indicated that KGB possesses anti-inflammatory and anti-oxidant effects, mediated by the inhibition of the mitogen-activated protein kinases (MAPKs) signaling pathway in LPS-induced RAW264.7 macrophages. KGB may represent a potential therapeutic agent for inflammatory and oxidative stress-related diseases.

The binding of kaempferol-3-O-rutinoside to vascular endothelial growth factor potentiates anti-inflammatory efficiencies in lipopolysaccharide-treated mouse macrophage RAW264.7 cells

BACKGROUND

Vascular Endothelial Growth Factors (VEGFs) are a group of growth factor in regulating development and maintenance of blood capillary. The VEGF family members include VEGF-A, placenta growth factor (PGF), VEGF-B, VEGF-C and VEGF-D. VEGF receptor activation leads to multiple complex signaling pathways, particularly in inducing angiogenesis. Besides, VEGF is produced by macrophages and T cells, which is playing roles in inflammation. In macrophages, VEGF receptor-3 (VEGFR-3) and its ligand VEGF-C are known to attenuate the release of pro-inflammatory cytokines.

METHODS

Immunoprecipitation and molecular docking assays showed the binding interaction of kaempferol-3-O-rutinoside and VEGF-C. Western blotting and qRT-PCR methods were applied to explore the potentiating effect of kaempferol-3-O-rutinoside in VEGF-C-mediated expressions of proteins and genes in endothelial cells and LPS-induced macrophages. Enzyme-linked immunosorbent assay (ELISA) was employed to reveal the release of proinflammatory cytokines in LPS-induced macrophages. Immunofluorescence assay was performed to determine the effect of kaempferol-3-O-rutinoside in regulating nuclear translocation of NF-κB p65 subunit in the VEGF-C-treated cultures. In addition, Transwell® motility assay was applied to detect the ability of cell migration after drug treatment in LPS-induced macrophages.

RESULTS

We identified kaempferol-3-O-rutinoside, a flavonoid commonly found in vegetable and fruit, was able to act on cultured macrophages in inhibiting inflammatory response, and the inhibition was mediated by its specific binding to VEGF-C. The kaempferol-3-O-rutinoside-bound VEGF-C showed high potency to trigger the receptor activation. In LPS-treated cultured macrophages, applied kaempferol-3-O-rutinoside potentiated inhibitory effects of exogenous applied VEGF-C on the secretions of pro-inflammatory cytokines, i.e. IL-6 and TNF-α, as well as expressions of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). This inhibition was in parallel to transcription and translocation of NF-κB. Moreover, the binding of kaempferol-3-O-rutinoside with VEGF-C suppressed the LPS-induced migration of macrophage.

CONCLUSION

Taken together, our results suggested the pharmacological roles of kaempferol-3-O-rutinoside in VEGF-C-mediated anti-inflammation.

DNA interaction, in vivo and in vitro cytotoxicity, reactive oxygen species, lipid peroxidation of -N, S donor Re(I) metal complexes

N, S donor ligands (L¹-L⁵){L¹-L⁵ = 1,5-bis(4-chlorophenyl)-3-(thiophen-2-yl)-4,5-dihydro-1H-pyrazole (L¹), 1-(4-bromophenyl)-5-(4-chlorophenyl)-3-(thiophen-2-yl)-4,5-dihydro-1H-pyrazole (L²), 5-(4-chlorophenyl)-3-(thiophen-2-yl)-1-(p-tolyl)-4,5-dihydro-1H-pyrazole (L³), 5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-(thiophen-2-yl)-4,5-dihydro-1H-pyrazole (L⁴), 5-(4-chlorophenyl)-1-(4-nitrophenyl)-3-(thiophen-2-yl)-4,5-dihydro-1H-pyrazole (L⁵)} were synthesized by Claisen-Schmidt condensation and characterized by spectrometric methods. The complexes (I-V) were synthesized by ligand combination followed by metal chelation. The binding of the rhenium complexes to Herrin sperm DNA was monitored by UV spectroscopy and viscosity measurements. The groove binding was suggested as the most possible mode, and the K_b values of the complexes were calculated. The mode of interaction was furthermore confirmed by molecular docking. Brine shrimp lethality and Saccharomyces cerevisiae cytotoxicity against the eukaryotic and prokaryotic cells showed the toxic nature of the synthesized compounds. All compounds were found active against S. cerevisiae, which was confirmed by increased ROS production, and DNA damage as compared to untreated yeast cell culture. The oxidative harm to cell structures was affirmed by lipid peroxidation. An antimicrobial study was carried out by estimating minimum inhibitory concentration against two Gram-positive and three Gram-negative bacteria. All complexes show good antiproliferative activity against the HCT 116 cell line. All synthesized complexes are biologically more active than the corresponding ligands.

LncRNA HOTAIR regulates lipopolysaccharide-induced cytokine expression and inflammatory response in macrophages

Long noncoding RNAs (lncRNAs) are emerging as major regulators of a variety of cell signaling processes. Many lncRNAs are expressed in immune cells and appear to play critical roles in the regulation of immune response. Here, we have investigated the potential role of a well-known lncRNA, HOTAIR, in inflammatory and immune response. Our studies demonstrate that HOTAIR expression is induced in immune cells (macrophages) upon treatment with lipopolysaccharide (LPS). Knockdown of HOTAIR reduces NF-κB-mediated inflammatory gene and cytokine expression in macrophages. Inhibition of NF-κB resulted in down-regulation of LPS-induced expression of HOTAIR as well as IL-6 and iNOS expression. We further demonstrated that HOTAIR regulates activation of NF-κB and its target genes (IL-6 and iNOS) expression via facilitating the degradation of IκBα. HOTAIR knockdown reduces the expression of NF-κB target gene expression via inhibiting the recruitment of NF-κB and associated cofactors at the target gene promoters. Taken together, our findings suggest that HOTAIR is a critical player in NF-κB activation in macrophages suggesting its potential functions in inflammatory and immune response.

Entangled Conditional Adversarial Autoencoder for de Novo Drug Discovery

Modern computational approaches and machine learning techniques accelerate the invention of new drugs. Generative models can discover novel molecular structures within hours, while conventional drug discovery pipelines require months of work. In this article, we propose a new generative architecture, entangled conditional adversarial autoencoder, that generates molecular structures based on various properties, such as activity against a specific protein, solubility, or ease of synthesis. We apply the proposed model to generate a novel inhibitor of Janus kinase 3, implicated in rheumatoid arthritis, psoriasis, and vitiligo. The discovered molecule was tested in vitro and showed good activity and selectivity.

Metabolomics to identify biomarkers and as a predictive tool in inflammatory diseases

There is an overwhelming need for a simple, reliable tool that aids clinicians in diagnosing, assessing disease activity and treating rheumatic conditions. Identification of biomarkers in partially understood inflammatory disorders has long been sought after as the Holy Grail of Rheumatology. Given the complex nature of inflammatory conditions, it has been difficult to earmark the potential biomarkers. Metabolomics, however, is promising in providing new insights into inflammatory conditions and also identifying such biomarkers. Metabolomic studies have generally revealed increased energy requirements for by-products of a hypoxic environment, leading to a characteristic metabolic fingerprint. Here, we discuss the significance of such studies and their potential as a biomarker.

FOXP3 DNA methylation levels as a potential biomarker in the development of periapical lesions

INTRODUCTION

Epigenetic mechanisms, such as DNA methylation, can modify gene expression patterns without changing the DNA sequence, comprising a tool that cells use to lock genes in the "off" position. Variations in the methylation profile have been correlated to a variety of human diseases. Here, we hypothesize that DNA methylation in immune response-related genes may contribute to the development of periapical lesions.

METHODS

The DNA methylation patterns of 22 immune response-related gene promoters were evaluated in 137 human periapical granulomas, 8 apical cysts, and 31 healthy gingival tissues from 2 independent cohorts using a pathway-specific real-time polymerase chain reaction array (EpiTect Methyl II; Qiagen Inc, Valencia, CA). Messenger RNA expression analysis by qualitative polymerase chain reaction was also performed. SABiosciences's hierarchical clustering and methylation (Qiagen, Valencia, CA) and Prism6 software (GraphPad Software, Inc, La Jolla, CA) were used for data analysis.

RESULTS

FOXP3 gene promoter showed the highest level of methylation in both periapical granulomas and apical cysts (P < .001), and methylation levels were inversely correlated with FOXP3 messenger RNA expression in the lesions. Furthermore, FOXP3 expression was prevalent in inactive lesions and was positively correlated with interleukin-10 and transforming growth factor beta levels.

CONCLUSIONS

Our results suggest that FOXP3 acts as a master switch governing the development and function of T-regulatory cells, whose functions include the inhibition of immune responses and temper inflammation. The observed differential methylation patterns of FOXP3 in periapical lesions may be crucial in determining its suppressive activity and may be involved in periapical lesion development.

Anti-inflammatory strategies in cartilage repair

Cartilage defects are normally concomitant with posttraumatic inflammation and pose a major challenge in cartilage repair. Due to the avascular nature of cartilage and its inability to surmount an inflammatory response, the cartilage is easily attacked by proinflammatory factors and oxidative stress; if left untreated, osteoarthritis may develop. Suppression of inflammation has always been a crux for cartilage repair. Pharmacological drugs have been successfully applied in cartilage repair; however, they cannot optimally work alone. This review article will summarize current pharmacological drugs and their application in cartilage repair. The development of extracellular matrix-based scaffolds and preconditioned tissue-specific stem cells will be emphasized because both of these tissue engineering components could contribute to an enhanced ability not only for cartilage regeneration but also for anti-inflammation. These strategies could be combined to boost cartilage repair under inflammatory conditions.

4-methoxycarbonyl curcumin: a unique inhibitor of both inflammatory mediators and periodontal inflammation

Chronic inflammatory diseases such as periodontitis have been associated with increased risk for various medical conditions including diabetes and cardiovascular disease. Endotoxin (lipopolysaccharide, LPS), derived from gram-negative periodonto-pathogens, can induce the local accumulation of mononuclear cells in the inflammatory lesion, increasing proinflammatory cytokines and matrix metalloproteinases (MMPs). This ultimately results in the destruction of periodontal connective tissues including alveolar bone. Curcumin is the principal dyestuff in the popular Indian spice turmeric and has significant regulatory effects on inflammatory mediators but is characterized by poor solubility and low bioactivity. Recently, we developed a series of chemically modified curcumins (CMCs) with increased solubility and zinc-binding activity, while retaining, or further enhancing, their therapeutic effects. In the current study, we demonstrate that a novel CMC (CMC 2.5: 4-methoxycarbonyl curcumin) has significant inhibitory effects, better than the parent compound curcumin, on proinflammatory cytokines and MMPs in in vitro, in cell culture, and in an animal model of periodontal inflammation. The therapeutic potential of CMC 2.5 and its congeners may help to prevent tissue damage during various chronic inflammatory diseases including periodontitis and may reduce the risks of systemic diseases associated with this local disorder.

Targeting inflammatory pathways in chronic lymphocytic leukemia

Despite recent major advances in leukemia research, the pathobiology of chronic lymphocytic leukemia (CLL) remains poorly understood. Herein we review the role chronic inflammation plays in the initiation and progression of CLL. The robust production of inflammatory cytokines and chemokines accompanied by activation of intra-cellular pro-inflammatory pathways, and the presence of somatic mutations that activate pro-inflammatory signaling pathways, suggest that chronic inflammation plays a pathophysiological role in this disease. Indeed, glucocorticoids and non-steroidal anti-inflammatory possess anti-tumor activity, and glucocorticoids have been broadly used to treat CLL and its complications. Recent clinical trials demonstrated that tyrosine kinase inhibitors, such as ibrutinib and the immune-modulatory agent lenalidomide, induced impressive clinical responses in CLL patients with relapsed or refractory disease. As those pro-inflammatory pathway inhibitors and immune modulating drugs proved to be effective in CLL, other agents with similar activities are currently investigated in clinical trials. New insights into the pathobiology of CLL and the development of novel classes of drugs will undoubtedly provide us with effective tools to treat and perhaps cure CLL.

Inhibition of p38 MAPK attenuates renal atrophy and fibrosis in a murine renal artery stenosis model

Renal artery stenosis (RAS) is an important cause of chronic renal dysfunction. Recent studies have underscored a critical role for CCL2 (MCP-1)-mediated inflammation in the progression of chronic renal damage in RAS and other chronic renal diseases. In vitro studies have implicated p38 MAPK as a critical intermediate for the production of CCL2. However, a potential role of p38 signaling in the development and progression of chronic renal disease in RAS has not been previously defined. We sought to test the hypothesis that inhibition of p38 MAPK ameliorates chronic renal injury in mice with RAS. We established a murine RAS model by placing a cuff on the right renal artery and treated mice with the p38 inhibitor SB203580 or vehicle for 2 wk. In mice treated with vehicle, the cuffed kidney developed interstitial fibrosis, tubular atrophy, and interstitial inflammation. In mice treated with SB203580, the RAS-induced renal atrophy was reduced (70% vs. 39%, P < 0.05). SB203580 also reduced interstitial inflammation and extracellular matrix deposition but had no effect on the development of hypertension. SB203580 partially blocked the induction of CCL2, CCL7 (MCP-3), CC chemokine receptor 2 (CCR2), and collagen 4 mRNA expression in the cuffed kidneys. In vitro, blockade of p38 hindered both TNF-α and TGF-β-induced CCL2 upregulation. Based on these observations, we conclude that p38 MAPK plays a critical role in the induction of CCL2/CCL7/CCR2 system and the development of interstitial inflammation in RAS.

Intracellular Signaling Pathways in Rheumatoid Arthritis

Dysfunctional intracellular signaling involving deregulated activation of the Janus Kinase/Signal Transducers and Activators of Transcription (JAK/STAT) and "cross-talk" between JAK/STAT and the stress-activated protein kinase/mitogen-activated protein kinase (SAPK/MAPK) and Phosphatidylinositide-3-Kinase/AKT/mammalian Target of Rapamycin (PI-3K/AKT/mTOR) pathways play a critical role in rheumatoid arthritis. This is exemplified by immune-mediated chronic inflammation, up-regulated matrix metalloproteinase gene expression, induction of articular chondrocyte apoptosis and "apoptosis-resistance" in rheumatoid synovial tissue. An important consideration in the development of novel therapeutics for rheumatoid arthritis will be the extent to which inhibiting these signal transduction pathways will sufficiently suppress immune cell-mediated inflammation to produce a lasting clinical remission and halt the progression of rheumatoid arthritis pathology. In that regard, the majority of the evidence accumulated over the past decade indicated that merely suppressing pro-inflammatory cytokine-mediated JAK/ STAT, SAPK/MAPK or PI-3K/AKT/mTOR activation in RA patients may be necessary but not sufficient to result in clinical improvement. Thus, targeting aberrant enzyme activities of spleen tyrosine kinase, sphingosine kinases-1, -2, transforming growth factor β-activated kinase-1, bone marrow kinase, and nuclear factor-κB-inducing kinase for intervention may also have to be considered.

A novel small molecule, HK-156, inhibits lipopolysaccharide-induced activation of NF-κB signaling and improves survival in mouse models of sepsis

AIM

To characterize a small molecule compound HK-156 as a novel inhibitor of the nuclear factor κB (NF-κB) signaling pathway.

METHODS

THP-1 monocytes and HEK293/hTLR4A-MD2-CD14 cells were tested. HK-156 and compound 809, an HK-156 analogue, were synthesized. A luciferase assay was used to evaluate the transcriptional activity of NF-κB. The levels of cytokines were measured with cytokine arrays, ELISA and quantitative PCR. An electrophoretic mobility shift assay (EMSA), immunofluorescence, Western blot and mass spectrometry were used to investigate the molecular mechanisms underlying the actions of the agent. BALB/c mice challenged with lipopolysaccharide (LPS, 15 mg/kg, ip) were used as a mouse experimental endotoxemia model.

RESULTS

In HEK293hTLR4/NF-κB-luc cells treated with LPS (1000 ng/mL), HK-156 inhibited the transcriptional activity of NF-κB in a concentration-dependent manner (IC₅₀=6.54 ± 0.37 μmol/L). Pretreatment of THP-1 monocytes with HK-156 (5, 10 and 20 μmol/L) significantly inhibited LPS-induced release and production of TNF-α and IL-1β, attenuated LPS-induced translocation of NF-κB into the nucleus and its binding to DNA, and suppressed LPS-induced phosphorylation and degradation of IκBα, and phosphorylation of IKKβ and TGFβ-activated kinase (TAK1). Meanwhile, HK-156 (5, 10 and 20 μmol/L) slightly suppressed LPS-induced activation of p38. The effect of HK-156 on LPS-induced activation of NF-κB signaling was dependent on thiol groups of cysteines in upstream proteins. In mouse models of sepsis, pre-injection of HK-156 (50 mg/kg, iv) significantly inhibited TNFα production and reduced the mortality caused by the lethal dose of LPS.

CONCLUSION

HK-156 inhibits LPS-induced activation of NF-κB signaling by suppressing the phosphorylation of TAK1 in vitro, and exerts beneficial effects in a mouse sepsis model. HK-156 may therefore be a useful therapeutic agent for treating sepsis.

The role of endosomal escape and mitogen-activated protein kinases in adenoviral activation of the innate immune response

Adenoviral vectors (AdV) activate multiple signaling pathways associated with innate immune responses, including mitogen-activated protein kinases (MAPKs). In this study, we investigated how systemically-injected AdVs activate two MAPK pathways (p38 and ERK) and the contribution of these kinases to AdV-induced cytokine and chemokine responses in mice. Mice were injected intravenously either with a helper-dependent Ad2 vector that does not express viral genes or transgenes, or with the Ad2 mutant ts1, which is defective in endosomal escape. We found that AdV induced rapid phosphorylation of p38 and ERK as well as a significant cytokine response, but ts1 failed to activate p38 or ERK and induced only a limited cytokine response. These results demonstrate that endosomal escape of virions is a critical step in the induction of these innate pathways and responses. We then examined the roles of p38 and ERK pathways in the innate cytokine response by administering specific kinase inhibitors to mice prior to AdV. The cytokine and chemokine response to AdV was only modestly suppressed by a p38 inhibitor, while an ERK inhibitor has mixed effects, lowering some cytokines and elevating others. Thus, even though p38 and ERK are rapidly activated after i.v. injection of AdV, cytokine and chemokine responses are mostly independent of these kinases.

Molecular structure, vibrational spectral studies of pyrazole and 3,5-dimethyl pyrazole based on density functional calculations

In this work, the experimental and theoretical vibrational spectra of pyrazole (PZ) and 3,5-dimethyl pyrazole (DMP) have been studied. FTIR and FT-Raman spectra of the title compounds in the solid phase are recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1), respectively. The structural and spectroscopic data of the molecules in the ground state are calculated using density functional methods (B3LYP) with 6-311+G** basis set. The vibrational frequencies are calculated and scaled values are compared with experimental FTIR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The complete vibrational assignments are performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SM) method. 13C and 1H NMR chemical shifts results are compared with the experimental values.

Laminar inflammatory gene expression in the carbohydrate overload model of equine laminitis

REASONS FOR PERFORMING STUDY

There is a need to assess the laminar inflammatory response in a laminitis model that more closely resembles clinical cases of sepsis-related laminitis than the black walnut extract (BWE) model.

OBJECTIVES

To determine if a similar pattern of laminar inflammation, characterised by proinflammatory cytokine expression, occurs in the CHO model of laminitis as has been previously reported for the BWE model.

METHODS

Sixteen horses administered 17.6 g of starch (85% corn starch/15% wood flour)/kg bwt via nasogastric (NG) tube were anaesthetised either after developing a temperature>38.9°C (DEV group, n=8) or at onset of Obel grade 1 lameness (OG1 group, n=8). Control horses (CON group, n=8) were anaesthetised 24 h after NG administration of 6 l of deionised water. Laminar tissue was collected from horses while under anaesthesia, followed by humane euthanasia. Real time-quantitative PCR was used to assess laminar mRNA concentrations of genes involved in inflammatory signalling.

RESULTS

Increased mRNA concentrations (P<0.05) for IL-1β, IL-6, IL-12p35, COX-2, E-selectin and ICAM-1 were present in laminae from horses with OG1 lameness but not at the DEV time, when compared to the CON horses. No differences between the groups were found for IL-2, IL-4, IL-10, TNF-α, IFN-γ or COX-1 at either the DEV or OG1 time points.

CONCLUSIONS

There was a notable difference in the temporal pattern of inflammatory events between the BWE and CHO models, with the majority of laminar inflammatory events appearing to occur at or near the onset of lameness in the CHO model, whereas many of these events peak earlier in the developmental stages in the BWE model. This suggests that, in addition to circulating inflammatory molecules, there may be a local phenomenon in the CHO model resulting in the simultaneous onset of multiple laminar events including endothelial activation, leucocyte emigration and proinflammatory cytokine expression.

POTENTIAL RELEVANCE

The similar (although somewhat delayed) inflammatory response in the CHO model of laminitis indicates that inflammatory signalling is a consistent entity in the pathophysiology of laminitis.

Anti-inflammatory effect of Rhus verniviflua Stokes by suppression of iNOS-mediated Akt and ERK pathways: in-vitro and in-vivo studies

OBJECTIVES

Rhus verniciflua Stokes (RVS), which has valuable medicinal properties, has for many years been prescribed for inflammation in east Asian medicine. Recent studies suggest that RVS has potent antioxidative, antitumor and anti-inflammatory properties.

METHODS

In this study, the anti-inflammatory effects of RVS in vitro and in vivo were investigated. The ethanol extract from RVS was partitioned with different solvents in order of increasing polarity.

KEY FINDINGS

Among the various extracts, the n-butanol extract displayed the most potent activity against nitric oxide and reactive oxygen species. The n-butanol extract also significantly regulates expression of nitric oxide synthase, which inhibits nitric oxide production at the transcriptional level in activated macrophages. Immunoblot analysis also showed that n-butanol extract suppresses the phosphorylation of extracellular signal-regulated kinase and Akt, suggesting that nitric oxide synthase suppression might be mediated via the extracellular signal-regulated kinase and Akt signaling pathways. This study also investigated whether n-butanol exerts an anti-inflammatory effect in an animal model. n-butanol extract significantly reduces carrageenan-induced mouse paw edema at 5 h.

CONCLUSIONS

These results suggest that RVS could be a promising candidate agent for inflammation prevention and combination therapy with anti-inflammatory drugs.

Suppression of Autoimmune Arthritis by Small Molecule Inhibitors of the JAK/STAT Pathway

A skewed ratio of pro-inflammatory to anti-inflammatory cytokines, elevated growth factor synthesis and T- and B-lymphocyte activation are 3 hallmarks of rheumatoid arthritis (RA) pathology. Interleukin-6 (IL-6), IL-7, IL-17, IL-12/IL-23 and growth factors, granulocyte macrophage-colony stimulating factor, IL-3, and erythropoietin activate the Janus Kinase/Signal Transducers and Activators of Transcription (JAK/STAT) pathway. Evidence showed that STAT protein phosphorylation (p-STAT) by activated JAKs is permissive for p-STAT to act as transcription factors by binding to STAT-responsive gene promoter sequences. This event is critical for perpetuating RA, in part, by up-regulating pro-inflammatory cytokine gene transcription. Activation of JAK/STAT by cytokines and growth factors can induce ‘cross-talk’ with other signaling pathways by which Stress-Activated Protein/Mitogen-Activated Protein Kinase (SAP/MAPK) and Phosphatidylinositide-3-Kinase (PI3K)-mediated signaling are also activated. JAK-specific small molecule inhibitors (SMIs) were developed to test whether JAK/STAT pathway blockade would regulate autoimmune-mediated inflammation. JAK-specific SMI blockade inhibited p-STAT induced by pro-inflammatory cytokines in vitro. Systemically administered JAK-specific SMI blockade also ameliorated biomarkers of inflammation in well-validated arthritis animal models. A few JAK-specific SMIs have made their way into RA clinical trials. In fact, the JAK3-specific SMI, CP-690,500 is the first JAK/STAT SMI to be assessed for clinical efficacy in a Phase III RA trial.

Development of extracellular signal-regulated kinase inhibitors

Activation of the extracellular signal-regulated kinase (ERK) signaling pathway has been implicated in mediating a diverse array of cellular functions including cell differentiation, proliferation, and inflammatory responses. In this review, we will discuss approaches to identify inhibitors of ERK proteins through targeting ATP-dependent and ATP-independent mechanisms. Given the diversity of ERK substrates and the importance of ERK signaling in normal cell functions, emphasis will be placed on the methods for identifying small molecular weight compounds that are substrate selective through ATP-independent interactions and potentially relevant to inflammatory processes. The approach for selective targeting of ERK substrates takes advantage of the basic understanding of unique ERK docking domains that are thought to interact with specific amino acid sequences on substrate proteins. Computer aided drug design (CADD) can facilitate the high throughput screening of millions of compounds with the potential for selective interactions with ERK docking domains and disruption of substrate interactions. As such, the CADD approach significantly reduces the number of compounds that will be evaluated in subsequent biological assays and greatly increases the hit rate of biologically active compounds. The potentially active compounds are evaluated for ERK protein binding using spectroscopic and structural biology methods. Compounds that show ERK interactions are then tested for their ability to inhibit substrate interactions and phosphorylation as well as ERK-dependent functions in whole organism or cell-based assays. Finally, the relevance of substrate-selective ERK inhibitors in the context of inflammatory disease will be discussed.

Involvement of JAK-STAT signaling/function after cyclophosphamide-induced bladder inflammation in female rats

Cytokines are upregulated in a variety of inflammatory conditions and cytokine/receptor interactions can activate JAK-STAT signaling. Previous studies demonstrated upregulation of numerous cytokines in the urinary bladder following cyclophosphamide (CYP)-induced cystitis. The role of JAK-STAT signaling in urinary bladder inflammation and referred somatic sensitivity has not been addressed. The contribution of JAK-STAT signaling pathways in CYP-induced bladder hyperreflexia and referred somatic hypersensitivity was determined in CYP-treated rats using a JAK2 inhibitor, AG490. Acute (4 h; 150 mg/kg ip), intermediate (48 h; 150 mg/kg ip), or chronic (75 mg/kg ip, once every 3 days for 10 days) cystitis was induced in adult, female Wistar rats with CYP treatment. Phosphorylation status of STAT-3 was increased in urinary bladder after CYP-induced cystitis (4 h, 48 h, chronic). Blockade of JAK2 with AG490 (5-15 mg/kg ip or intravesical) significantly (P < or = 0.05) reduced bladder hyperreflexia and hind paw sensitivity in CYP-treated rats. These studies demonstrate a potential role for JAK-STAT signaling pathways in bladder hyperreflexia and referred pain induced by CYP-induced bladder inflammation.

Transition metal complexes with pyrazole-based ligands, Part 29: Reactions of zinc(II) and mercury(II) thiocyanate with 4-acetyl-3-amino-5-methylpyrazole

The work is concerned with the crystal and molecular structures of zinc(II) and mercury(II) complexes with 4-acetyl-3-amino-5-methyl-pyrazole (aamp) of the coordination formulae [Zn(NCS)2(aamp)2[ and (Haamp)2[Hg(SCN)4]. The zinc(II) complex was obtained by the reaction of a warm methanolic solution of aamp with a mixture of zinc(II) nitrate and ammonium thiocyanate, whereas the mercury(II) complex was prepared by the reaction of a warm ethanolic solution of aamp and a warm, slightly acidified aqueous solution of [Hg(SCN)4]2-. Both complexes have a tetrahedral geometry, which in the case of zinc complex is formed by monodentate coordination of two aamp molecules and two isothiocyanate groups. The Zn(II) and Hg(II) atoms have significantly deformed coordination geometry. In both crystal structures the pyrazole derivative has a planar form, probably stabilized by an intramolecular N-H???O hydrogen bond. Apart from the X-ray structural analysis, the isolated complexes were characterized by elemental analysis, IR spectroscopy, conductometric measurements and thermal analysis.