Search

Ericameria nauseosa (Pall. ex Pursh) G.L. Nesom & G.I. Baird) is used in traditional medicine to treat various diseases; however, little is known about the immunomodulatory activity of essential oil from this plant. Thus, we isolated essential oil from the aerial parts of E. nauseosa and evaluated their chemical composition and biological activity. Compositional analysis of E. nauseosa essential oil revealed that the main (>2%) components were γ-decalactone (13.3%), cryptone (9.4%), terpinen-4-ol (9.3%), (E)-methyl cinnamate (6.0%), T-cadinol (4.7%), spathulenol (3.6%), 8Z-2,3-dihydromatricaria ester (3.1%), β-phellandrene (3.0%), p-cymen-8-ol (2.2%), 3-ethoxy-2-cycloocten-1-one (2.2%), and trans-p-menth-2-en-1-ol (2.1%). Distinctive features were the lactones (up to 15%) and polyacetylenes (up to 3.1%), including (2Z,8Z)-matricaria ester and 8Z-2,3-dihydromatricaria ester. A comparison with other reported E. nauseosa essential oil samples showed that our samples were distinct from those collected in other areas of the country; however, they did have the most similarity to one sample collected in North Central Utah. Pharmacological studies showed that E. nauseosa essential oil activated human neutrophil Ca2+ influx, which desensitized these cells to subsequent agonist-induced functional responses. Based on our previously reported data that nerolidol, β-pinene, spathulenol, sabinene, and γ-terpinene were active in human neutrophils, these compounds are the most likely constituents contributing to this immunomodulatory activity. However, the relatively high amount of polyacetylenes may also contribute, as these compounds have been characterized as potent immunomodulators. [ABSTRACT FROM AUTHOR]

Echinacea purpurea (L.) Moench is a medicinal plant commonly used for the treatment of upper respiratory tract infections, the common cold, sore throat, migraine, colic, stomach cramps, and toothaches and the promotion of wound healing. Based on the known pharmacological properties of essential oils (EOs), we hypothesized that E. purpurea EOs may contribute to these medicinal properties. In this work, EOs from the flowers of E. purpurea were steam-distilled and analyzed by gas chromatography–mass spectrometry (GC–MS), GC with flame-ionization detection (GC–FID), and chiral GC–MS. The EOs were also evaluated for in vitro antimicrobial and innate immunomodulatory activity. About 87 compounds were identified in five samples of the steam-distilled E. purpurea EO. The major components of the E. purpurea EO were germacrene D (42.0 ± 4.61%), α-phellandrene (10.09 ± 1.59%), β-caryophyllene (5.75 ± 1.72%), γ-curcumene (5.03 ± 1.96%), α-pinene (4.44 ± 1.78%), δ-cadinene (3.31 ± 0.61%), and β-pinene (2.43 ± 0.98%). Eleven chiral compounds were identified in the E. purpurea EO, including α-pinene, sabinene, β-pinene, α-phellandrene, limonene, β-phellandrene, α-copaene, β-elemene, β-caryophyllene, germacrene D, and δ-cadinene. Analysis of E. purpurea EO antimicrobial activity showed that they inhibited the growth of several bacterial species, although the EO did not seem to be effective for Staphylococcus aureus. The E. purpurea EO and its major components induced intracellular calcium mobilization in human neutrophils. Additionally, pretreatment of human neutrophils with the E. purpurea EO or (+)-δ-cadinene suppressed agonist-induced neutrophil calcium mobilization and chemotaxis. Moreover, pharmacophore mapping studies predicted two potential MAPK targets for (+)-δ-cadinene. Our results are consistent with previous reports on the innate immunomodulatory activities of β-caryophyllene, α-phellandrene, and germacrene D. Thus, this study identified δ-cadinene as a novel neutrophil agonist and suggests that δ-cadinene may contribute to the reported immunomodulatory activity of E. purpurea. [ABSTRACT FROM AUTHOR]

Agastache urticifolia (Benth.) Kuntze (horsemint), Achillea millefolium L. (yarrow), and Perideridia gairdneri (Hook. & Arn.) Mathias (yampah) are native, culturally important plants that grow in the subalpine meadows of Montana. Analysis of the composition of essential oils extracted from these plants showed that the main components of essential oils obtained from flowers and leaves of A. urticifolia (designated as AUF/AUL) were menthone (2.7/25.7%), isomenthone (2.6/29.1%), pulegone (78.9/28.8%), and limonene (4.2/6.2%), whereas essential oils obtained from the inflorescence of A. millefolium (designated as AMI) were high in α-thujone (17.1%) and β-thujone (14.9%), 1,8-cineole (17.0%), camphor (13.0%), sabinene (7.0%), guaia-3,9-dien-11-ol (3.2%), and terpinen-4-ol (2.5%). Essential oils obtained from the inflorescence of P. gairdneri (designated as PGI) contained high amounts of dillapiole (30.3%), p-cymen-8-ol (14.1%), terpinolene (12.0%), 4-hydroxy-4-methyl-cyclohex-2-enone (6.2%), and γ-terpinene (2.4%). Evaluation of their immunomodulatory activity demonstrated that essential oils extracted from all of these plants could activate human neutrophils with varying efficacy. Analysis of individual components showed that dillapiole activated human neutrophil intracellular Ca2+ flux ([Ca2+]i) (EC50 = 19.3 ± 1.4 μM), while α-thujone, β-thujone, menthone, isomenthone, and pulegone were inactive. Since dillapiole activated neutrophils, we also evaluated if it was able to down-regulate neutrophil responses to subsequent agonist activation and found that pretreatment with dillapiole inhibited neutrophil activation by the chemoattractant fMLF (IC50 = 34.3 ± 2.1 μM). Pretreatment with P. gairdneri essential oil or dillapiole also inhibited neutrophil chemotaxis induced by fMLF, suggesting these treatments could down-regulate human neutrophil responses to inflammatory chemoattractants. Thus, dillapiole may be a novel modulator of human neutrophil function. [ABSTRACT FROM AUTHOR]

Propolis is a resinous mixture of substances collected and processed from various botanical sources by honeybees. Black poplar (Populus balsamifera L.) buds are one of the primary sources of propolis. Despite their reported therapeutic properties, little is known about the innate immunomodulatory activity of essential oils from P. balsamifera and propolis. In the present studies, essential oils were isolated from the buds of P. balsamifera and propolis collected in Montana. The main components of the essential oil from P. balsamifera were E-nerolidol (64.0%), 1,8-cineole (10.8%), benzyl benzoate (3.7%), α-terpinyl acetate (2.7%), α-pinene (1.8%), o-methyl anisol (1.8%), salicylaldehyde (1.8%), and benzyl salicylate (1.6%). Likewise, the essential oil from propolis was enriched with E-nerolidol (14.4%), cabreuva oxide-VI (7.9%), α-bisabolol (7.1%), benzyl benzoate (6.1%), β-eudesmol (3.6%), T-cadinol (3.1%), 2-methyl-3-buten-2-ol (3.1%), α-eudesmol (3.0%), fokienol (2.2%), nerolidol oxide derivative (1.9%), decanal (1.8%), 3-butenyl benzene (1.5%), 1,4-dihydronaphthalene (1.5%), selina-4,11-diene (1.5%), α-cadinol (1.5%), linalool (1.4%), γ-cadinene (1.4%), 2-phenylethyl-2-methyl butyrate (1.4%), 2-methyl-2-butenol (1.3%), octanal (1.1%), benzylacetone (1.1%), and eremoligenol (1.1%). A comparison between P. balsamifera and propolis essential oils demonstrated that 22 compounds were found in both essential oil samples. Both were enriched in E-nerolidol and its derivatives, including cabreuva oxide VI and nerolidol oxides. P. balsamifera and propolis essential oils and pure nerolidol activated Ca2+ influx in human neutrophils. Since these treatments activated neutrophils, the essential oil samples were also evaluated for their ability to down-regulate the neutrophil responses to subsequent agonist activation. Indeed, treatment with P. balsamifera and propolis essential oils inhibited subsequent activation of these cells by the N-formyl peptide receptor 1 (FPR1) agonist fMLF and the FPR2 agonist WKYMVM. Likewise, nerolidol inhibited human neutrophil activation induced by fMLF (IC50 = 4.0 μM) and WKYMVM (IC50 = 3.7 μM). Pretreatment with the essential oils and nerolidol also inhibited human neutrophil chemotaxis induced by fMLF, again suggesting that these treatments down-regulated human neutrophil responses to inflammatory chemoattractants. Finally, reverse pharmacophore mapping predicted several potential kinase targets for nerolidol. Thus, our studies have identified nerolidol as a potential anti-inflammatory modulator of human neutrophils. [ABSTRACT FROM AUTHOR]

Grindelia squarrosa (Pursh) Dunal is used in traditional medicine for treating various diseases; however, little is known about the immunomodulatory activity of essential oils from this plant. Thus, we isolated essential oils from the flowers (GEOFl) and leaves (GEOLv) of G. squarrosa and evaluated the chemical composition and innate immunomodulatory activity of these essential oils. Compositional analysis of these essential oils revealed that the main components were α-pinene (24.7 and 23.2% in GEOFl and GEOLv, respectively), limonene (10.0 and 14.7%), borneol (23.4 and 16.6%), p-cymen-8-ol (6.1 and 5.8%), β-pinene (4.0 and 3.8%), bornyl acetate (3.0 and 5.1%), trans-pinocarveol (4.2 and 3.7%), spathulenol (3.0 and 2.0%), myrtenol (2.5 and 1.7%), and terpinolene (1.7 and 2.0%). Enantiomer analysis showed that α-pinene, β-pinene, and borneol were present primarily as (−)-enantiomers (100% enantiomeric excess (ee) for (−)-α-pinene and (−)-borneol in both GEOFl and GEOLv; 82 and 78% ee for (−)-β-pinene in GEOFl and GEOLv), while limonene was present primarily as the (+)-enantiomer (94 and 96 ee in GEOFl and GEOLv). Grindelia essential oils activated human neutrophils, resulting in increased [Ca2+]i (EC50 = 22.3 µg/mL for GEOFl and 19.4 µg/mL for GEOLv). In addition, one of the major enantiomeric components, (−)-borneol, activated human neutrophil [Ca2+]i (EC50 = 28.7 ± 2.6), whereas (+)-borneol was inactive. Since these treatments activated neutrophils, we also evaluated if they were able to down-regulate neutrophil responses to subsequent agonist activation and found that treatment with Grindelia essential oils inhibited activation of these cells by the N-formyl peptide receptor 1 (FPR1) agonist fMLF and the FPR2 agonist WKYMVM. Likewise, (−)-borneol inhibited FPR-agonist-induced Ca2+ influx in neutrophils. Grindelia leaf and flower essential oils, as well as (−)-borneol, also inhibited fMLF-induced chemotaxis of human neutrophils (IC50 = 4.1 ± 0.8 µg/mL, 5.0 ± 1.6 µg/mL, and 5.8 ± 1.4 µM, respectively). Thus, we identified (−)-borneol as a novel modulator of human neutrophil function. [ABSTRACT FROM AUTHOR]

Despite their reported therapeutic properties, not much is known about the immunomodulatory activity of essential oils present in Artemisia species. We isolated essential oils from the flowers and leaves of five Artemisia species: A. tridentata, A. ludoviciana, A. dracunculus, A. frigida, and A. cana. The chemical composition of the Artemisia essential oil samples had similarities and differences as compared to those previously reported in the literature. The main components of essential oils obtained from A. tridentata, A. ludoviciana, A. frigida, and A. cana were camphor (23.0–51.3%), 1,8-cineole (5.7–30.0%), camphene (1.6–7.7%), borneol (2.3–14.6%), artemisiole (1.2–7.5%), terpinen-4-ol (2.0–6.9%), α-pinene (0.8–3.9%), and santolinatriene (0.7–3.5%). Essential oils from A. dracunculus were enriched in methyl chavicol (38.8–42.9%), methyl eugenol (26.1–26.4%), terpinolene (5.5–8.8%), (E/Z)-β-ocimene (7.3–16.0%), β-phellandrene (1.3–2.2%), p-cymen-8-ol (0.9–2.3%), and xanthoxylin (1.2–2.2%). A comparison across species also demonstrated that some compounds were present in only one Artemisia species. Although Artemisia essential oils were weak activators of human neutrophils, they were relatively more potent in inhibiting subsequent neutrophil Ca2+ mobilization with N-formyl peptide receptor 1 (FPR1) agonist fMLF- and FPR2 agonist WKYMVM, with the most potent being essential oils from A. dracunculus. Further analysis of unique compounds found in A. dracunculus showed that farnesene, a compound with a similar hydrocarbon structure as lipoxin A4, inhibited Ca2+ influx induced in human neutrophils by fMLF (IC50 = 1.2 μM), WKYMVM (IC50 = 1.4 μM), or interleukin 8 (IC50 = 2.6 μM). Pretreatment with A. dracunculus essential oils and farnesene also inhibited human neutrophil chemotaxis induced by fMLF, suggesting these treatments down-regulated human neutrophil responses to inflammatory chemoattractants. Thus, our studies have identified farnesene as a potential anti-inflammatory modulator of human neutrophils. [ABSTRACT FROM AUTHOR]

N‐formyl peptide receptors (FPR1, FPR2, and FPR3) play key roles in the regulation of inflammatory processes, and recently, it was demonstrated that FPR1 and FPR2 have a dual role in the progression/suppression of some cancers. Therefore, FPRs represent an important therapeutic target for the treatment of both cancer and inflammatory diseases. Previously, we identified selective or mixed FPR agonists with pyridazinone or pyridinone scaffolds showing a common 4‐(bromophenyl)acetamide fragment, which was essential for activity. We report here new pyrazole and pyrazolone derivatives as restricted analogues of the above 6‐membered compounds, all exhibiting the same 4‐bromophenylacetamide side chain. Most new products had low or absent FPR agonist activity, suggesting that the pyrazole nucleus was not appropriate for FPR agonists. This hypothesis was confirmed by molecular modeling studies, which highlighted that the five‐membered scaffold was responsible for a worse arrangement of the molecules in the receptor binding site. [ABSTRACT FROM AUTHOR]

Formyl peptide receptors (FPRs) are expressed on a variety of leukocytes and play important roles in inflammation. Thus, FPR antagonists may represent novel therapeutics for modulating innate immunity and treating inflammatory diseases. Previously, 1 H -pyrrol-2(5 H )-ones were reported to be potent and competitive FPR1 antagonists. In the present studies, 42 additional 1 H -pyrrol-2(5 H )-one analogs were evaluated for FPR1 antagonist activity. We identified a number of novel competitive FPR1 antagonists that inhibited N -formylmethionyl-leucyl-phenylalanine ( f MLF)-induced intracellular Ca 2+ mobilization in FPR1-transfected HL60 cells and effectively competed with WKYMVm-FITC for binding to FPR1 in FPR1-transfected RBL cells. The most active pyrroles inhibited human neutrophil Ca 2+ flux, chemotaxis, and adhesion to human epithelial cells, with the most potent being compounds 14 (4-benzoyl-1-hexyl-3-hydroxy-5-(4-hydroxy-3-methoxyphenyl)-2,5-dihydro-1 H -pyrrol-2-one) and 17 (4-benzoyl-5-(2,5-dimethoxyphenyl)-3-hydroxy-1-(2-methoxyethyl)-2,5-dihydro-1 H -pyrrol-2-one). In addition, these FPR1 antagonists inhibited f MLF-induced phosphorylation of extracellular signal-regulated kinases (ERK1/2) in FPR1-RBL cells, differentiated HL-60 cells, and human neutrophils. Most of the antagonists were specific for FPR1 and did not inhibit WKYMVM/WKYMVm-induced intracellular Ca 2+ mobilization in FPR2-HL60 cells, FPR3-HL60 cells, or interleukin 8-induced Ca 2+ flux in human neutrophils. Moreover, molecular modeling showed that the active pyrroles had a significantly higher degree of similarity with the FPR1 antagonist pharmacophore template as compared to inactive analogs. Thus, the 4-aroyl-3-hydroxy-5-phenyl-1 H -pyrrol-2(5 H )-one scaffold represents an important backbone for the development of novel FPR1 antagonists and could provide important clues for understanding the molecular structural requirements of FPR1 antagonists. [ABSTRACT FROM AUTHOR]

Activation of neutrophils by Ferula iliensis essential oils enriched in (E/Z)‐propenyl sec‐butyl disulfides is mediated by activation of transient receptor potential V1 channels. Essential oil extracts from Ferula iliensis have been used traditionally in Kazakhstan for treatment of inflammation and other illnesses. Because little is known about the biologic activity of these essential oils that contributes to their therapeutic properties, we analyzed their chemical composition and evaluated their phagocyte immunomodulatory activity. The main components of the extracted essential oils were (E)‐propenyl sec‐butyl disulfide (15.7–39.4%) and (Z)‐propenyl sec‐butyl disulfide (23.4–45.0%). Ferula essential oils stimulated [Ca2+]i mobilization in human neutrophils and activated ROS production in human neutrophils and murine bone marrow phagocytes. Activation of human neutrophil [Ca2+]i flux by Ferula essential oils was dose‐dependently inhibited by capsazepine, a TRPV1 channel antagonist, indicating that TRPV1 channels mediate this response. Furthermore, Ferula essential oils stimulated Ca2+ influx in TRPV1 channel–transfected HEK293 cells and desensitized the capsaicin‐induced response in these cells. Additional molecular modeling with known TRPV1 channel agonists suggested that the active component is likely to be (Z)‐propenyl sec‐butyl disulfide. Our results provide a cellular and molecular basis to explain at least part of the beneficial therapeutic properties of FEOs. [ABSTRACT FROM AUTHOR]

ABSTRACT [ABSTRACT FROM AUTHOR]

Formyl peptide receptor 1 (FPR1) regulates a wide variety of neutrophil functional responses and plays an important role in inflammation and the pathogenesis of various diseases. To date, a variety of natural and synthetic molecules have been identified as FPR1 ligands. Here, we review current knowledge on natural products and natural product-inspired small molecules reported to antagonize and/or inhibit the FPR1-mediated responses. Based on this literature, additional screening of selected commercially available natural compounds for their ability to inhibit f MLF-induced Ca 2 + mobilization in human neutrophils and FPR1 transfected HL-60 cells, and pharmacophore modeling, natural products with potential as FPR1 antagonists are considered and discussed in this review. The identification and characterization of natural products that antagonize FPR1 activity may have potential for the development of novel therapeutics to limit or alter the outcome of inflammatory processes. [ABSTRACT FROM AUTHOR]

N -Formyl peptide receptors (FPRs: FPR1, FPR2, and FPR3) are G protein-coupled receptors that play key roles in modulating immune cells. FPRs represent potentially important therapeutic targets for the development of drugs that could enhance endogenous anti-inflammation systems associated with various pathologies, thereby reducing the progression of inflammatory conditions. Previously, we identified 2-arylacetamide pyridazin-3(2 H )-ones as FPR1- or FPR2-selective agonists, as well as a large number of FPR1/FPR2-dual agonists and several mixed-agonists for the three FPR isoforms. Here, we report a new series of 2-arylacetamido-4-aniline pyridazin-3(2 H )-ones substituted in position 5 as a further development of these FPR agonists. Chemical manipulation presented in this work resulted in mixed FPR agonists 8a , 13a and 27b , which had EC 50 values in nanomolar range. In particular, compound 8a showed a preference for FPR1 (EC 50 = 45 nM), while 13a and 27b showed a moderate preference for FPR2 (EC 50 = 35 and 61 nM, respectively). Thus, these compounds may represent valuable tools for studying FPR activation and signaling. [ABSTRACT FROM AUTHOR]

N -Formyl peptide receptors (FPRs) are G protein-coupled receptors (GPCRs) that play critical roles in inflammatory reactions, and FPR-specific interactions can possibly be used to facilitate the resolution of pathological inflammatory reactions. We here report the synthesis and biological evaluation of six pairs of chiral ureidopropanamido derivatives as potent and selective formyl peptide receptor-2 (FPR2) agonists that were designed starting from our lead agonist ( S )-3-(1 H -indol-3-yl)-2-[3-(4-methoxyphenyl)ureido]- N -[[1-(5-methoxy-2-pyridinyl)cyclohexyl]methyl]propanamide (( S )- 9a ). The new compounds were obtained in overall yields considerably higher than ( S )- 9a . Several of the new compounds showed agonist properties comparable to that of ( S )- 9a along with higher selectivity over FPR1. Molecular modeling was used to define chiral recognition by FPR2. In vitro metabolic stability of selected compounds was also assessed to obtain preliminary insight on drug-like properties of this class of compounds. [ABSTRACT FROM AUTHOR]

Formyl peptide receptors (FPRs) are G protein-coupled receptors (GPCRs) expressed on a variety of cell types. Because FPRs play an important role in the regulation of inflammatory reactions implicated in disease pathogenesis, FPR antagonists may represent novel therapeutics for modulating innate immunity. Previously, 4 H -chromones were reported to be potent and competitive FPR1 antagonists. In the present studies, 96 additional chromone analogs, including related synthetic and natural isoflavones were evaluated for FPR1 antagonist activity. We identified a number of novel competitive FPR1 antagonists that inhibited f MLF-induced intracellular Ca 2+ mobilization in FPR1-HL60 cells and effectively competed with WKYMVm-FITC for binding to FPR1 in FPR1-HL60 and FPR1-RBL cells. Compound 10 (6-hexyl-2-methyl-3-(1-methyl-1 H -benzimidazol-2-yl)-4-oxo-4 H -chromen-7-yl acetate) was found to be the most potent FPR1-specific antagonist, with binding affinity K i ∼ 100 nM. These chromones inhibited Ca 2+ flux and chemotaxis in human neutrophils with nanomolar-micromolar IC 50 values. In addition, the most potent novel FPR1 antagonists inhibited f MLF-induced phosphorylation of extracellular signal-regulated kinases (ERK1/2) in FPR1-RBL cells. These antagonists were specific for FPR1 and did not inhibit WKYMVM/WKYMVm-induced intracellular Ca 2+ mobilization in FPR2-HL60 cells, FPR3-HL60 cells, RBL cells transfected with murine Fpr1, or interleukin 8-induced Ca 2+ flux in human neutrophils and RBL cells transfected with CXC chemokine receptor 1 (CXCR1). Moreover, pharmacophore modeling showed that the active chromones had a significantly higher degree of similarity with the pharmacophore template as compared to inactive analogs. Thus, the chromone/isoflavone scaffold represents a relevant backbone for development of novel FPR1 antagonists. [ABSTRACT FROM AUTHOR]

A new series of pyridazinone-based thioderivatives and pyridazine analogs was synthesizedand tested for their ability to bind to the three human formyl peptide receptor (FPR) isoforms (FPR1,FPR2, and FPR3) and to activate intracellular calcium mobilization and chemotaxis in human neutrophils.Among the pyridazin-3(2H)-one derivatives tested, analogs 8b and 8c were mixed FPR1/FPR2 agonists,with median effective concentration values in the micromolar range, and were able to activate chemotaxisand Ca2+ flux in human neutrophils in the low micromolar range. Molecular docking studies showed thatinteraction of a ligand with Arg205 of FPR1 is important for FPR1 agonist activity. For FPR2, differences inactivity between oxygen-containing compounds and their thio-analogs were due to steric bulkiness ofsulfur-containing groups. Drug Dev Res 74 : 259-271, 2013. [ABSTRACT FROM AUTHOR]

Little is known about the immunomodulatory activity of essential oils isolated from Juniperus species. Thus, we isolated essential oils from the cones and leaves of eight juniper species found in Montana and in Kazakhstan, including J. horizontalis, J. scopolorum, J. communis, J. seravschanica, J. sabina, J. pseudosabina, J. pseudosabina subsp. turkestanica, and J. sibirica. We report here the chemical composition and innate immunomodulatory activity of these essential oils. Compositional analysis of the 16 samples of Juniper essential oils revealed similarities and differences between our analyses and those previously reported for essential oils from this species. Our studies represent the first analysis of essential oils isolated from the cones of four of these Juniper species. Several essential oil samples contained high levels of cedrol, which was fairly unique to three Juniper species from Kazakhstan. We found that these essential oils and pure (+)-cedrol induced intracellular Ca2+ mobilization in human neutrophils. Furthermore, pretreatment of human neutrophils and N-formyl peptide receptor 1 and 2 (FPR1 and FPR2) transfected HL60 cells with these essential oils or (+)-cedrol inhibited agonist-induced Ca2+ mobilization, suggesting these responses were desensitized by this pretreatment. In support of this conclusion, pretreatment with essential oils from J. seravschanica cones (containing 16.8% cedrol) or pure (+)-cedrol inhibited human neutrophil chemotaxis to N-formyl peptide. Finally, reverse pharmacophore mapping predicted several potential kinase targets for cedrol. Thus, our studies have identified cedrol as a novel neutrophil agonist that can desensitize cells to subsequent stimulation by N-formyl peptide. [ABSTRACT FROM AUTHOR]

Abstract: The leaves of Artemisia species have been traditionally used for prevention and treatment of a number of diseases. In this study, five polysaccharide fractions (designated A-I–A-V) were isolated from the leaves of Artemisia tripartita Rydb. by the sequential use of hot-water extraction, ethanol precipitation, ultra-filtration, and chromatography. The homogeneity and average molecular weight of each fraction were determined by high performance size-exclusion chromatography. Sugar composition analysis revealed that Artemisia polysaccharides consisted primarily of xylose, glucose, arabinose, galactose, and galactosamine. Moreover, all fractions contained at least 3.4% sulfate, and fractions A-II–A-V contained an arabinogalactan type II structure. All fractions exhibited macrophage-activating activity, enhancing production of intracellular reactive oxygen species and release of nitric oxide, interleukin 6, interleukin 10, tumor necrosis factor α, and monocyte chemotactic protein 1. In addition, all fractions exhibited scavenging activity for reactive oxygen species generated enzymatically or produced extracellularly by human neutrophils. Finally, fractions A-I and A-V exhibited complement-fixing activity. Taken together, our results provide a molecular basis to explain at least part of the beneficial therapeutic effects of Artemisia extracts, and suggest the possibility of using Artemisia polysaccharides as an immunotherapeutic adjuvant. [Copyright &y& Elsevier]

Abstract: Tanacetum vulgare L. (Tansy) has been extensively used in folk medicine for treatment of a variety of medical disorders. In the present study, we isolated and purified four acidic polysaccharide fractions (designated T-I to T-IV) from Tansy florets by the sequential use of hot-water extraction, ethanol precipitation, ultra-filtration, anion-exchange, and size-exclusion chromatography. The average M r of fractions T-I through T-IV was estimated to be 326, 151, 64 and 9 kDa, respectively, as determined by high performance size-exclusion chromatography analysis. Sugar composition analysis revealed that Tansy polysaccharides consisted primarily of galacturonic acid, galactose, arabinose, and rhamnose. Fractions T-II through T-IV contained an arabinogalactan type II structure, as determined by reaction with Yariv reagent. High M r fractions T-I and T-II exhibited potent macrophage/monocyte-activating activity, enhancing production of reactive oxygen species (ROS), nitric oxide (NO), and tumor necrosis factor α (TNF-α) by J774.A1 murine macrophages, and activating nuclear factor κB (NF-κB) in THP-1 human monocytes. In addition, Tansy polysaccharides stimulated human neutrophil function by greatly enhancing neutrophil myeloperoxidase (MPO) release. Furthermore, the low M r fraction T-IV had potent complement-fixing activity, which may also contribute to the anti-inflammatory and would-healing properties of Tansy extracts. Taken together, our results provide a molecular basis to explain at least part of the beneficial therapeutic effects of Tansy extracts, and support the concept of using Tansy polysaccharides as an immunotherapeutic adjuvant. [Copyright &y& Elsevier]

Rhododendron (Ericaceae) extracts contain flavonoids, chromones, terpenoids, steroids, and essential oils and are used in traditional ethnobotanical medicine. However, little is known about the immunomodulatory activity of essential oils isolated from these plants. Thus, we isolated essential oils from the flowers and leaves of R. albiflorum (cascade azalea) and analyzed their chemical composition and innate immunomodulatory activity. Compositional analysis of flower (REOFl) versus leaf (REOLv) essential oils revealed significant differences. REOFl was comprised mainly of monoterpenes (92%), whereas sesquiterpenes were found in relatively low amounts. In contrast, REOLv was primarily composed of sesquiterpenes (90.9%), with a small number of monoterpenes. REOLv and its primary sesquiterpenes (viridiflorol, spathulenol, curzerene, and germacrone) induced intracellular Ca2+ mobilization in human neutrophils, C20 microglial cells, and HL60 cells transfected with N-formyl peptide receptor 1 (FPR1) or FPR2. On the other hand, pretreatment with these essential oils or component compounds inhibited agonist-induced Ca2+ mobilization and chemotaxis in human neutrophils and agonist-induced Ca2+ mobilization in microglial cells and FPR-transfected HL60 cells, indicating that the direct effect of these compounds on [Ca2+]i desensitized the cells to subsequent agonist activation. Reverse pharmacophore mapping suggested several potential kinase targets for these compounds; however, these targets were not supported by kinase binding assays. Our results provide a cellular and molecular basis to explain at least part of the beneficial immunotherapeutic properties of the R. albiflorum essential oils and suggest that essential oils from leaves of this plant may be effective in modulating some innate immune responses, possibly by inhibition of neutrophil migration. [ABSTRACT FROM AUTHOR]

Synthetic and natural ionophores have been developed to catalyze ion transport and have been shown to exhibit a variety of biological effects. We synthesized 24 aza- and diaza-crown ethers containing adamantyl, adamantylalkyl, aminomethylbenzoyl, and ε-aminocaproyl substituents and analyzed their biological effects in vitro. Ten of the compounds (8, 10–17, and 21) increased intracellular calcium ([Ca2+]i) in human neutrophils, with the most potent being compound 15 (N,N'-bis[2-(1-adamantyl)acetyl]-4,10-diaza-15-crown-5), suggesting that these compounds could alter normal neutrophil [Ca2+]i flux. Indeed, a number of these compounds (i.e., 8, 10–17, and 21) inhibited [Ca2+]i flux in human neutrophils activated by N-formyl peptide (fMLF). Some of these compounds also inhibited chemotactic peptide-induced [Ca2+]i flux in HL60 cells transfected with N-formyl peptide receptor 1 or 2 (FPR1 or FPR2). In addition, several of the active compounds inhibited neutrophil reactive oxygen species production induced by phorbol 12-myristate 13-acetate (PMA) and neutrophil chemotaxis toward fMLF, as both of these processes are highly dependent on regulated [Ca2+]i flux. Quantum chemical calculations were performed on five structure-related diaza-crown ethers and their complexes with Ca2+, Na+, and K+ to obtain a set of molecular electronic properties and to correlate these properties with biological activity. According to density-functional theory (DFT) modeling, Ca2+ ions were more effectively bound by these compounds versus Na+ and K+. The DFT-optimized structures of the ligand-Ca2+ complexes and quantitative structure-activity relationship (QSAR) analysis showed that the carbonyl oxygen atoms of the N,N'-diacylated diaza-crown ethers participated in cation binding and could play an important role in Ca2+ transfer. Thus, our modeling experiments provide a molecular basis to explain at least part of the ionophore mechanism of biological action of aza-crown ethers. [ABSTRACT FROM AUTHOR]

Hypericum L. (Hypericaceae) extracts have been used for their therapeutic effects; however, not much is known about the immunomodulatory activity of essential oils extracted from this plant. We isolated essential oils from the flowers and leaves of H. perforatum and analyzed their chemical composition and innate immunomodulatory activity. Analysis of flower (HEOFl) versus leaf (HEOLv) essential oils using gas chromatography–mass spectrometry revealed that HEOFl was comprised mainly of monoterpenes (52.8%), with an abundance of oxygenated monoterpenes, including cis-p-menth-3-en-1,2-diol (9.1%), α-terpineol (6.1%), terpinen-4-ol (7.4%), and limonen-4-ol (3.2%), whereas the sesquiterpenes were found in trace amounts. In contrast, HEOLv was primarily composed of sesquiterpenes (63.2%), including germacrene D (25.7%) and β-caryophyllene (9.5%). HEOLv also contained oxygenated monoterpenes, including terpinen-4-ol (2.6%), while monoterpene hydrocarbons were found in trace amounts. Both HEOFl and HEOLv inhibited neutrophil Ca2+ mobilization, chemotaxis, and reactive oxygen species (ROS) production, with HEOLv being much more active than HEOFl. Furthermore, the pure sesquiterpenes germacrene D, β-caryophyllene, and α-humulene also inhibited these neutrophil responses, suggesting that these compounds represented the active components of HEOLv. Although reverse pharmacophore mapping suggested that potential protein targets of germacrene D, β-caryophyllene, bicyclogermacrene, and α-humulene could be PIM1 and mitogen-activated protein kinase (MAPK)-activated protein kinase 2 (MAPKAK2), a kinase binding affinity assay did not support this finding, implying that other biological targets are involved. Our results provide a cellular and molecular basis to explain at least part of the beneficial immunotherapeutic properties of the H. perforatum essential oils. [ABSTRACT FROM AUTHOR]

Organosulfur compounds are bioactive components of garlic essential oil (EO), mustard oil, Ferula EOs, asafoetida, and other plant and food extracts. Traditionally, garlic (Allium sativum) is used to boost the immune system; however, the mechanisms involved in the putative immunomodulatory effects of garlic are unknown. We investigated the effects of garlic EO and 22 organosulfur compounds on human neutrophil responses. Garlic EO, allyl propyl disulfide, dipropyl disulfide, diallyl disulfide, and allyl isothiocyanate (AITC) directly activated Ca2+ flux in neutrophils, with the most potent being AITC. Although 1,3-dithiane did not activate neutrophil Ca2+ flux, this minor constituent of garlic EO stimulated neutrophil reactive oxygen species (ROS) production. In contrast, a close analog (1,4-dithiane) was unable to activate neutrophil ROS production. Although 1,3-dithiane-1-oxide also stimulated neutrophil ROS production, only traces of this oxidation product were generated after a 5 h treatment of HL60 cells with 1,3-dithiane. Evaluation of several phosphatidylinositol-3 kinase (PI3K) inhibitors with different subtype specificities (A-66, TGX 221, AS605240, and PI 3065) showed that the PI3K p110δ inhibitor PI 3065 was the most potent inhibitor of 1,3-dithiane-induced neutrophil ROS production. Furthermore, 1,3-dithiane enhanced the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), glycogen synthase kinase 3 α/β (GSK-3α/β), and cAMP response element binding (CREB) protein in differentiated neutrophil-like HL60 cells. Density functional theory (DFT) calculations confirmed the reactivity of 1,3-dithiane vs. 1,4-dithiane, based on the frontier molecular orbital analysis. Our results demonstrate that certain organosulfur compounds can activate neutrophil functional activity and may serve as biological response modifiers by augmenting phagocyte functions. [ABSTRACT FROM AUTHOR]

• Synthesis of new pyridinone and pyrimidinone derivatives bearing a phenylacetamido chain at N-2 of the scaffold. • Identification of a new series of FPR agonists with EC 50 values in the sub-μM range. • The most part of compounds are mixed FPR1/FPR2 agonists with a preference for FPR2 isoform. • Compounds 2a , EC3 and EC10 were evaluated in a in vivo model of rheumatoid arthritis. • Compound 2a is able to completely control pain hypersensitivity p.o. at 30 mg/Kg. The resolution of inflammation is an active response involving the interaction of pro-resolving mediators with specific receptors, such as N -formyl peptide receptor 2 (FPR2). FPRs represent potentially important therapeutic targets for the treatment of some pathologies, including asthma and rheumatoid arthritis. Previously, we identified selective or mixed FPR agonists with a pyridazin-3(2 H)-one scaffold, all containing a 4-bromophenylacetamide fragment at N-2. The most effective compounds in this series were EC3 , a potent mixed FPR1/FPR2/FPR3 agonist, and EC10 , which had a preference for FPR1. We report here a new series of pyridinone and pyrimidindione derivatives containing the 4-(bromophenyl)acetamide substituent that was essential for activity in the pyridazinone series. All new compounds were evaluated for FPR agonist activity in HL60 cells transfected with FPR1 or FPR2 and in human neutrophils. While most of the pyridinone derivatives had reasonable FPR agonist activity in the submicromolar/micromolar range, the pyrimidindione derivatives were less active. Compound 2a (N-(4-bromophenyl)-2-[3-cyano-5-(3-methoxyphenyl)-6-methyl-2-oxopyridin-1(2H)-yl]acetamide) was the most active pyridinone derivative and had a 10-fold preference for FPR2 (EC 50 = 120 nM) versus FPR1 (EC 50 = 1.6 μM). To assess their therapeutic activity, compounds 2a , EC3 , and EC10 were evaluated in vivo using a rat model of rheumatoid arthritis. All three compounds increased the pain threshold and reduced pain hypersensitivity in the treated rats versus control rats, although 2a and EC10 were much more effective than EC3. Thus, these FPR agonists represent potential leads to develop for the treatment of inflammatory diseases such as rheumatoid arthritis. [ABSTRACT FROM AUTHOR]