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PubMed1990

[Observations and research on an extract of Inula viscosa Ait ].

The folk medical tradition ascribes to Inula viscosa (a suffrutescent plant of Compositae widely spread along the Mediterranean basin) balsamic, antipyretic, antiphlogistic and antiseptic properties. Pharmacological test on rabbits, made hyperpyretic in laboratory, gave satisfactory antipyretic results. Gas chromatographical separation from a high-boiling fraction of seven azulenes, two of them identified as 1,4-dimethyl-azulene (about 50% and chamazulene (32%), confirmed the antiphlogistic action ascribed to the plant. By the present research (solvent extraction, thin layer chromatography and gas chromatography are described in detail) eucalyptol was identified in a fraction of essential oil obtained from fresh leaves of the plant. This datum supports the balsamic and antiseptic properties of Inula viscosa Ait.

Animals↗
PubMedDate not supplied

Effect of guaiazulene on some cytochrome P450 activities. Implication in the metabolic activation and hepatotoxicity of paracetamol.

The in vitro and in vivo effect of guaiazulene, a natural azulene derivative, on rat hepatic cytochrome P450 (CYP) is investigated. Furthermore, paracetamol hepatotoxicity is induced in rats and the activity of specific cytochrome P450 forms, involved in the metabolic activation of paracetamol to the toxic metabolite N-acetyl-p-benzoquinone imine (NAPQI) is examined, after the administration of guaiazulene, using diagnostic cytochrome P450 substrates. It is found that guaiazulene inhibited considerably CYP1A2 and CYP2B1 and had a weak effect on CYP1A1 in rat hepatic microsomal fractions. Guaiazulene administered to rats did not produce any macroscopic toxic effect and caused no change of liver weight, microsomal protein and total cytochrome P450 content. Guaiazulene inhibited CYP1A2 activity in rats with or without paracetamol intoxication. Considering that CYP1A2 participates in the formation of NAPQI, as well as in the metabolic activation of several toxic and carcinogenic compounds, these results, in combination with the antioxidant activity of guaiazulene that we have found in previous investigations, indicate potential useful applications of guaiazulene.

Acetaminophen↗
PubMed1999

Diagnostic and therapeutic applications of azulenyl nitrone spin traps.

Azulenyl nitrones have been recently demonstrated to constitute a new class of nitrone-based spin traps with the unprecedented capacity to tag free radicals by yielding characteristically colored and highly visible diamagnetic (and paramagnetic) spin adducts. In addition, a comparison of the oxidation potentials of azulenyl nitrones such as 1 and congeners to those of conventional nitrone spin traps previously investigated as potential antioxidant therapeutics such as N-tert-butyl-alpha-phenylnitrone and its related ortho-sodium sulfonate reveals that the azulene-derived spin traps are far more readily oxidized. These special features render azulenyl nitrones of interest with regard to both their distinct ability to engender the convenient use of colorimetric detection to monitor free radical-mediated oxidative stress in biological systems, and to their potentially enhanced efficacy as neuroprotective antioxidants vs. those conventional nitrone spin traps earlier examined as such. Herein is reported an overview of recent developments pertaining to the use of azulenyl nitrones in the detection of oxidative stress in animal models of amyotrophic lateral sclerosis and stroke, and to their neuroprotective activity in animal models of Parkinson's disease, stroke and neurodegeneration within the retina.

Amyotrophic Lateral Sclerosis↗
PubMed2003

Effect of antiproliferative agents on vascular function in normal and in vitro balloon-injured porcine coronary arteries.

Local infusion of antiproliferative agents following coronary balloon angioplasty is used in vivo. This study examined the effects of the antiproliferative agents paclitaxel (5-beta, 20-Epoxy-1,2-alpha,4,7-beta,10-beta,13-alpha-Hexahydroxy-Tax-11-en-9-one 4,10-Diacetate 2_Benzoate 13-Ester with (2R,3S)-N-Benzoyl-3-Phenylisoserine; 10 and 50 microM), farnesyl protein transferase inhibitor III (FPT III, (E,E)-2-[2-Oxo-2-[(3,7,11-trimethyl-2,6,10-dodecatrienyl) oxy] amino] ethyl] phosphonic acid, (2,2-dimethyl-1-oxopropoxy) methyl ester, sodium); 10 and 25 microM), perillyl alcohol (4-isopropenyl-cyclohexenecarbinol; 1 and 2 mM) and Van 10/4 (Decahydro-1,1,4,7-tetramethyl-1H-cycloprop[e]azulen-4-o-[2-(3-methylpent-2-enoyl)-fucopyranoside]; 10 and 25 microM) on normal and in vitro balloon-injured porcine coronary arteries. Short-term (30 min) incubation had no effect on contraction or relaxation. Overnight incubation with 25 microM Van 10/4-attenuated contraction while perillyl alcohol abolished contractility completely. Endothelium-dependent relaxation was significantly attenuated by the higher concentration of paclitaxel, FPT III and Van 10/4. Stretch injury significantly enhanced sensitivity to 3-morpholinosydnonimine (SIN-1) while attenuating relaxation to calcimycin. Drug incubation (15 min) had no effect on these responses. In conclusion, paclitaxel, FPT III and Van 10/4 have no detrimental effects on vascular function after short-term administration to normal or stretch-injured arteries.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2006

Locally administered antiproliferative drugs inhibit hypercontractility to serotonin in balloon-injured pig coronary artery.

Although drugs such as sirolimus and paclitaxel are effective in reducing restenosis, their effects on vascular function are often overlooked. In this study, we have examined the effects of local delivery of several anti-restenotic drugs given in vivo after balloon injury on in vitro vascular contraction and relaxation 28 days after injury. Paclitaxel (50 microM), the farnesyl protein transferase inhibitor L744 (25 microM), sirolimus (25 microM) and Van 10/4 (decahydro-1,1,4,7-tetramethyl-1H-cycloprop[e]azulen-4-o-[2-(3-methylpent-2-enoyl)-fucopyranoside]; 25 microM) were delivered to porcine coronary arteries in vivo and the arteries removed 28 days later. Contractions to KCl and 5-hydroxytryptamine (5-HT) and relaxations to calcimycin and 3-morpholinosydnonimine (SIN-1) were measured in control (LCx) and balloon-injured (LAD) rings. In vehicle-infused coronary arteries, contraction to KCl and 5-HT was significantly enhanced 28 days after balloon injury, while the response to calcimycin had recovered fully, indicating endothelial regrowth. The response to SIN-1 was unchanged. None of the four drugs tested had any effect on the enhanced response to KCl 28 days after injury or on recovery of the calcimycin response. The hyper-responsiveness to 5-HT was eliminated by sirolimus, Van 10/4 and L744, but not paclitaxel. This study demonstrates that local drug infusion with structurally different antiproliferative drugs at the time of balloon angioplasty does not affect endothelial recovery and may in some cases prevent hyper-responsiveness to constrictor agents.

Angioplasty, Balloon, Coronary↗
PubMed2003

First isocyanoazulene and its homoleptic complexes.

An efficient synthesis of remarkably stable 6-isocyanoazulene (CN6Az), the first nonbenzenoid organic isocyanide, is described. Its superb pi-accepting potential as a ligand was demonstrated through cyclic voltammetry studies on the binary complexes [Cr(CN6Az)6]0/+. The paramagnetic shift patterns for [Cr(CN6Az)6]+, the only azulenic pi-system studied by paramagnetic NMR, suggest that Cr(dpi) --> CN6Az(ppi*) electron delocalization involves both rings of the azulenyl substituents in [Cr(CN6Az)6]+. This conclusion is supported by density functional theory calculations on the complex [Cr(CN6Az)6][BF4].

Azulenes↗
PubMed1997

Antioxidant activity of guaiazulene and protection against paracetamol hepatotoxicity in rats.

The effect of guaiazulene, a lipophilic azulene derivative widely found in nature, on radical-mediated processes is examined. The ability of guaizulene to inhibit rat hepatic microsomal membrane lipid peroxidation and to scavenge hydroxyl radicals, as well as to interact with 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), was estimated. It was found that guaiazulene can inhibit lipid peroxidation very significantly, having an IC50 value of 9.8 microM. It can also scavenge hydroxyl radicals and interact with DPPH. The protection afforded by guaiazulene to rats with paracetamol-induced liver injury was also investigated. Paracetamol hepatotoxicity is caused by the reactive metabolite N-acetyl-p-benzoquinone imine (NAPQI), which causes oxidative stress and glutathione (GSH) depletion. Hepatic cytosolic protein, GSH, glutathione transferase and glutathione reductase levels are determined as indices of hepatic injury with or without the administration of guaiazulene. It was found that all parameters affected by paracetamol are restored to normal by guaiazulene treatment, while the administration of guaiazulene alone has no effect on the performed tests compared with the control values. It was concluded that the significant protection against paracetamol-induced GSH depletion and hepatic damage afforded by guaiazulene is probably connected with its antioxidant activity. A molecular mechanism of action of guaiazulene is suggested.

Acetaminophen↗
PubMed2005

Comparative study between the effects of photodynamic therapy and conventional therapy on microbial reduction in ligature-induced peri-implantitis in dogs.

BACKGROUND: Progressive peri-implant bone losses, which are accompanied by inflammatory lesions in the soft tissues, are referred to as peri-implantitis. The aim of this study was to compare the effects of photodynamic therapy (PDT) and conventional technique on microbial reduction in ligature-induced peri-implantitis in dogs. METHODS: Eighteen third premolars from nine Labrador retriever dogs were extracted and the implants were submerged. After osseointegration, peri-implantitis was induced. After 4 months, ligature was removed and natural bacterial plaque was allowed to form for another 4 months. The animals were then randomly divided into two groups. In the conventional group, they were treated using mucoperiosteal flaps for scaling the implant surface and chlorexidine (conventional) irrigation. In the PDT group, only mucoperiosteal scaling was carried out before photodynamic therapy. Inside the peri-implant pocket, a paste-based azulene photosensitizer was placed and then a GaAlAs low-power laser (lambda=660 nm, P=40 mW, E=7.2 J for 3 minutes) was used. Microbiological samples were obtained before and immediately after treatment. Before treatment, one implant was removed and analyzed by scanning electron microscopy to validate the contamination. RESULTS: The results of this study showed that Prevotella sp., Fusobacterium sp., and S. Beta-haemolyticus were significantly reduced for both groups. After treatment, no significant differences were observed between the groups. CONCLUSION: These findings suggest that photodynamic therapy is a non-invasive method that could be used to reduce microorganisms in peri-implantitis.

Animals↗
PubMedDate not supplied

Cytotoxic activity of azulenequinones against human oral tumor cell lines.

We investigated twenty-seven azulenequinone derivatives for their relative cytotoxicity against three human normal cell lines (HGF, HPC, HPLF) and four human tumor cell lines (HSG, HSC-2, HSC-3, HL-60). Parent 1,5-azulenequinone showed potent and some tumor-specific cytotoxicity. Halogenated derivatives of 1,5- and 1,7-azulenequinone showed potent cytotoxicity, but lower tumor-specific cytotoxicity. In contrast to other azulenequinones, amino derivatives such as 3-amino-1,5- and 1, 7-azulenequinones showed relatively lower cytotoxic activity. The 3-Phenoxy-1,5-azuleneqinone derivative showed higher cytotoxicity than the 3-phenoxy-1, 7-azulenequinone derivative. 1,5- and 1,7-Azulenequinones generally showed higher cytotoxicity, as compared with tropolones and azulene derivatives. 3- (3-Guaiazulenyl)-1, 5-azulenequinone [12] and 7-isopropyl-3- (4-methylanilino)-2-methyl- 1, 5-azulenequinone [24] showed a relatively higher TS value and induced apoptosis (internucleosomal DNA fragmentation, activation of caspases 3, 8 and 9) in HL-60 and HSC-2 cells, possibly via the activation of both mitochondria-independent (extrinsic) and -dependent (intrinsic) pathways. Western blot analysis showed that [24] slightly increased the intracellular concentration of pro-apoptotic proteins (Bad, Bax) in HSC-2 cells, whereas [12] was much less active. None of the twenty-seven azulenequinones showed anti-HIV activity. These results suggest [12] and [24] as possible candidates for future cancer chemotherapy.

Anti-HIV Agents↗
PubMedDate not supplied

Effect of marzulene on the restitution of rat gastric mucosa after NaOH-induced injury.

BACKGROUND/AIMS: The purpose of this study was to assess the effect of marzulene (L-glutamine plus azulene) on the repair of NaOH-induced gastric mucosal injury in rats. METHODOLOGY: Gastric mucosal injury was induced with intragastric instillation of 3.0 ml of 5% NaOH for 1 minute. From 2 days after the operation, the rats were orally given chow pellets containing 0%, 0.25%, or 0.5% of marzulene for 25 weeks. RESULTS: Oral administration of marzulene at both dosages significantly increased the mucosal heights of the fundic and antral mucosa at week 25. Marzulene also increased the labeling indices of the fundic and antral epithelial cells, but not the mucosal blood flow. CONCLUSIONS: These findings indicate that marzulene stimulates repair mechanisms of rat gastric mucosa after NaOH injury. This effect of marzulene may be associated with a stimulation of gastric epithelial cell proliferation.

Administration, Oral↗
PubMed2001

Multimode-photochromism based on strongly coupled dihydroazulene and diarylethene.

Synthesis and photophysical/photochemical investigations of 1,8a-dihydro-2,3-bis(2,5-dimethy-3-thienyl)-azulene-1,1-dicarbonitrile (1A) and 1,8a-dihydro-2,3-diphenylazulene-1,1-dicarbonitrile (2A) are reported. The photoprocesses and thermal reactions of systems 1 and 2 were studied by time-resolved and steady-state techniques under various conditions. The dihydroazulene (DHA)-dithienylethene (DTE) conjugate 1A is photochemically converted into the dihydrothienobenzothiophene (DHB) isomer 1C and the vinylheptafulvene (VHF) isomer 1B. System 2 exhibits exclusively DHA/VHF photochromism. For both systems the VHF form thermally reverts back into the DHA form. Their rate constant (kB-->A) increases with the solvent polarity and the relaxation kinetics proceed by means of an activation barrier of 65-80 kJ mol(-1); kB-->A and the activation parameters of the isomerisation reactions are rather similar. The photostationary state of the 1A-->1B and 1A-->1C photoisomerisation is sensitive to the irradiation wavelength. The concept of cycloswitching is discussed.

Journal Article↗
PubMed1992

Platelet aggregation inhibiting and anticoagulant effects of oligoamines, XVII: Oligoamines with fluorescent properties. Part A: Fluorescent bridged nitrogen functions.

Eleven dimethanamines and one disydnonimine with fluorescent properties have been synthesized. All of them show antiplatelet activities (IC50, Born-test) in concentrations between 14-75 mumol/L. Five of them inhibited fibrin formation induced by thromboplastin by more than 75% in a 200 mu molar concentration. Both effect do not run parallel. The most space consuming fluorophores show the smallest inhibition of the platelet aggregation. Best results were obtained with an azulene, acenaphthene or naphthalene moiety between the two basic nitrogen functions.

Anticoagulants↗
PubMed2004

Structural properties and photophysical behavior of conformationally constrained hexapeptides functionalized with a new fluorescent analog of tryptophan and a nitroxide radical quencher.

The influence of the conformational properties on the photophysics of two de novo designed hexapeptides was studied by spectroscopic measurements (ir, NMR, steady-state, and time resolved fluorescence) and molecular mechanics calculations. The peptide sequences comprise two nonproteinogenic residues: a beta-(1-azulenyl)-L-alanine (Aal) residue, obtained by formally functionalizing the Ala side chain with the azulene chromophore, and a Calpha-tetrasubstituted alpha-amino acid (TOAC), incorporating a nitroxide group in a cycloalkyl moiety. Aal represents a new fluorescent, quasi-isosteric Trp analog and TOAC a stable radical species, frequently used as a paramagnetic probe in biochemical studies. The peptide chains differ in the sequence position of the two probes and are heavily based on Aib (alpha-aminoisobutyric acid) residues to generate conformationally restricted helical structures, as confirmed by both spectroscopic and computational results. The conformationally controlled, excited state interactions, determining the photophysical relaxation of the Aal*/TOAC pair, are also discussed.

Antioxidants↗
PubMed2005

Cytotoxic activity and constituents of the volatile oil from the roots of Patrinia scabra Bunge.

The volatile oil from the roots of Patrinia scabra Bunge was isolated by steam distillation, and separated into four major fractions (Fr. A-D) by means of column chromatography. A total of 39 compounds (1-39) were identified by GC/MS analysis, and evaluated for their in vitro cytotoxic activities against human ovarian carcinoma cells (HO-8910) and human hepatoma cells (Bel-7402) (Table 1). Fr. A showed the strongest inhibitory effect on HO-8910 (IC50 = 21 microg/ml) and Bel-7402 cells (16 mcirog/ml), whereas Fr. B was the least active (>100 microg/ml). By comparison of the constituents of the four fractions, we assume that the cytotoxicity of the volatile oil of P. scabra is mainly due to the lignans and azulenes, rather than to caryophyllene oxide I (18). Our results suggest that the volatile oil of P. scabra possesses potent and tumor-specific cytotoxicity, and could serve as a possible candidate for future cancer chemotherapy.

Antineoplastic Agents, Phytogenic↗
PubMed2006

A review of the bioactivity and potential health benefits of chamomile tea (Matricaria recutita L.).

Chamomile (Matricaria recutita L., Chamomilla recutita L., Matricaria chamomilla) is one of the most popular single ingredient herbal teas, or tisanes. Chamomile tea, brewed from dried flower heads, has been used traditionally for medicinal purposes. Evidence-based information regarding the bioactivity of this herb is presented. The main constituents of the flowers include several phenolic compounds, primarily the flavonoids apigenin, quercetin, patuletin, luteolin and their glucosides. The principal components of the essential oil extracted from the flowers are the terpenoids alpha-bisabolol and its oxides and azulenes, including chamazulene. Chamomile has moderate antioxidant and antimicrobial activities, and significant antiplatelet activity in vitro. Animal model studies indicate potent antiinflammatory action, some antimutagenic and cholesterol-lowering activities, as well as antispasmotic and anxiolytic effects. However, human studies are limited, and clinical trials examining the purported sedative properties of chamomile tea are absent. Adverse reactions to chamomile, consumed as a tisane or applied topically, have been reported among those with allergies to other plants in the daisy family, i.e. Asteraceae or Compositae.

Beverages↗
PubMed2000

Chemical modification of hemoglobin improves biocatalytic oxidation of PAHs.

Chemical modifications on human hemoglobin were performed with the aim to change both surface and active-site hydrophobicities. The modifications included covalent coupling of poly(ethylene)glycol (5000 MW) on free amino groups and the methyl esterification of free carboxylic groups. The modified hemoglobin was assayed for the oxidation of 11 polycyclic aromatic hydrocarbons (PAHs) and 2 organosulfur aromatic compounds. Acenaphthene, anthracene, azulene, benzo(a)pyrene, fluoranthene, fluorene, phenanthrene, and pyrene were transformed to their respective quinones, while for chrysene and biphenyl no biocatalytic reaction could be detected. Dibenzothiophene and thianthrene were oxidized to form sulfoxides. The doubly modified hemoglobin, PEG-Met-hemoglobin, showed up to 10 times higher activity than the unmodified protein. The kinetic constants show that the PEG-Met-hemoglobin has a significantly higher catalytic efficiency. The equilibrium substrate binding constants for unmodified and PEG-Met-modified hemoglobis and hemoglobin show that this catalytic enhancement could be attributed to the affinity increase for hydrophobic substrates in the modified protein.

Catalysis↗
PubMed2003

Interaction of 7-azatryptophan and beta-(1-azulenyl)-alanine with a nitroxyl radical.

Aal and 7-Atrp, quasi-isosteric with Trp, have been inserted together with a TOAC residue in two 3(10)-helical, model hexapeptides. The interaction of photoexcited AA1 and 7-Atrp with the nitroxide group of TOAC was investigated by time resolved EPR. Both peptides showed nitroxide spin polarized signals revealing that an intramolecular interaction takes places between the excited chromophore and the free radical moiety. The observation of a spin polarized signal in emission for AA1 is accounted for by the formation of triplet azulene by radical promoted enhanced inter system crossing (EISC).

Alanine↗
PubMed1992

Prevention of malodor from intraoral gauze tamponade with the topical use of clindamycin.

Azulene ointment with a small dose of clindamycin was used topically in eight patients with maxillary cancer with the intent to inhibit the malodor that originates from a gauze tamponade applied to the postoperative maxillary bony defect. The malodor was either markedly decreased or eliminated in all cases. Concurrent with the decrease or elimination of the malodor, anaerobic microorganisms such as Bacteroides and Peptostreptococcus, which are considered to be involved in the generation of malodor, also became undetectable.

Administration, Topical↗