In efforts to identify novel small molecules with antiinflammatory properties, we discovered a unique series of tetracyclic indenoquinoxaline derivatives that inhibited lipopolysaccharide (LPS)-induced nuclear factor-B/activating protein 1 activation. Compound IQ-1 (11H-indeno[1,2-b]quinoxalin-11-one oxime) was found to be a potent, noncytotoxic inhibitor of pro-inflammatory cytokine [interleukin (IL)-1␣, IL-1␤, IL-6, IL-10, tumor necrosis factor (TNF)-␣, interferon-␥, and granulocyte-macrophage colony-stimulating factor] and nitric oxide production by human and murine monocyte/macrophages. Three additional potent inhibitors of cytokine production were identified through further screening of IQ-1 analogs. The sodium salt of IQ-1 inhibited LPS-induced TNF-␣ and IL-6 production in MonoMac-6 cells with IC 50 values of 0.25 and 0.61 M, respectively. Screening of 131 protein kinases revealed that derivative IQ-3 [11H-indeno[1,2-b]quinoxalin-11-one-O-(2-furoyl)oxime]was a specific inhibitor of the c-Jun N-terminal kinase (JNK) family, with preference for JNK3. This compound, as well as IQ-1 and three additional oxime indenoquinoxalines, were found to be high-affinity JNK inhibitors with nanomolar binding affinity and ability to inhibit c-Jun phosphorylation. Furthermore, docking studies showed that hydrogen bonding interactions of the active indenoquinoxalines with Asn152, Gln155, and Met149 of JNK3 played an important role in enzyme binding activity. Finally, we showed that the sodium salt of IQ-1 had favorable pharmacokinetics and inhibited the ovalbumin-induced CD4 ϩ T-cell immune response in a murine delayed-type hypersensitivity model in vivo. We conclude that compounds with an indenoquinoxaline nucleus can serve as specific small-molecule modulators for mechanistic studies of JNKs as well as a potential leads for the development of anti-inflammatory drugs.

We screened a chemolibrary of drug-like molecules for their ability to activate reactive oxygen species (ROS) production in murine phagocytes, and we identified 26 novel compounds with potent neutrophil activating properties. We used substructure screening, fragment-focusing, and structure-activity relationship analyses to further probe the parent library and defined at least two groups of activators of ROS production in murine neutrophils: t-butyl benzene and thiophene-2-amide-3-carboxylic ester derivatives. Further studies of the active compounds revealed 11 compounds that activated ROS production in human neutrophils, and six of these compounds also activated intercellular Ca 2ϩ mobilization and chemotaxis in human neutrophils. Of the latter compounds, compound 14 (1,3-benzodioxolane-5-carboxylic acid 4Ј-benzyloxy-3Ј-methoxybenzylidene-hydrazide) activated neutrophils at nanomolar concentrations, and Ca 2ϩ mobilization was inhibited by pertussis toxin and N-t-butoxycarbonyl-Phe-Leu-Phe-Leu-Phe (Boc-2), an antagonist of formyl peptide receptors (FPR/FPRL1).Likewise, activation by compound 14 was desensitized after N-formyl-Met-Leu-Phe pretreatment. Similar biological activities were found for compound 104 (1,3-benzodioxolane-5-carboxylic acid 3Ј-bromo-5Ј-ethoxy-4Ј-hydroxybenzylidenehydrazide), an analog of compound 14. Furthermore, conformational analysis of the activators of chemotaxis and Ca Based on these results, we conclude that compounds 14 and 104 represent novel small-molecule agonists of FPR. These studies enhance our understanding of FPR ligand/receptor interactions and structure/activity relationships of phagocyte agonists.

In this review, we focus on the medicinal drugs from humus matter such as peat, sapropel, and mumie. The most clinically available medicines, containing peat and sapropel extracts, are Torfot, Tolpa Peat Preparation (TPP), Peloidodistillate, Humisol, Peloidin, FiBS, and Eplir. Much attention in the review is concentrated on mumie composition, its pharmacological properties, and new pharmacological drugs with mumie (Shilagen, Abana, Cystone, Diabecon 400, EveCare, Geriforte, Lukol, Pilex, Rumalava, Tentex forte, Nefrotec, Adrenotone, Siotone, La-Tone Gold, Andro-Surge, Solanova Libidoplex). It was concluded that therapeutic properties of crude extracts from peat, sapropel, and mumie have similarity to the ones of fulvic and humic acids. They are antibacterial, antitoxic, antiradical, antiulcerogenic, antiarthritic, immunomodulatory, and antiinflammatory properties. Possible directions for better development of new drugs from humus matter are discussed. Drug Dev.

Human neutrophil elastase (HNE) is an important therapeutic target for treatment of pulmonary diseases. Previously, we identified novel N-benzoylindazole derivatives as potent, competitive, and pseudoirreversible HNE inhibitors. Here, we report further development of these inhibitors with improved potency, protease selectivity, and stability compared to our previous leads. Introduction of a variety of substituents at position 5 of the indazole resulted in the potent inhibitor 20f (IC50~10 nM), and modifications at position 3 resulted the most potent compound in this series, the 3-CN derivative 5b (IC50= 7 nM); both derivatives demonstrated good stability and specificity for HNE versus other serine proteases. Molecular docking of selected N-benzoylindazoles into the HNE binding domain suggested that inhibitory activity depended on geometry of the ligand-enzyme complexes. Indeed, the ability of a ligand to form a Michaelis complex and favorable conditions for proton transfer between Hys57, Asp102 and Ser195 both affected activity.

Epilobium angustifolium has been traditionally used to treat of a number of diseases; however, not much is known regarding its effect on innate immune cells. We found that extracts of E. angustifolium activated functional responses in neutrophils and monocyte/macrophages. Activity‐guided fractionation, followed by mass spectroscopy and NMR analysis, resulted in the identification of oenothein B as the primary component responsible for phagocyte activation. Oenothein B, a dimeric hydrolysable tannin, dose‐dependently induced a number of phagocyte functions in vitro, including intracellular Ca2+ flux, production of reactive oxygen species (ROS), chemotaxis, nuclear factor (NF)‐κB activation, and proinflammatory cytokine production. Furthermore, oenothein B was active in vivo, inducing keratinocyte chemoattractant (KC) production and neutrophil recruitment to the peritoneum after intraperitoneal administration. The ability of oenothein B to modulate phagocyte functions in vitro and in vivo suggests that this compound is responsible for at least part of the therapeutic properties of E. angustifolium extracts. This work was supported in part by NIH grants RR‐020185 and RR‐016455 and NIH contract HHSN266200400009C.