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British Journal of Pharmacology Jun 1986In cascade perfusion and superfusion experiments on rabbit tissues, when acetylcholine (ACh) was introduced into the circuit so as to perfuse the aorta under perfusion...
In cascade perfusion and superfusion experiments on rabbit tissues, when acetylcholine (ACh) was introduced into the circuit so as to perfuse the aorta under perfusion with noradrenaline (NA), the effluent relaxed the transverse aortic strip which had been denuded of endothelium. The effluent from the perfused aorta which was capable of relaxing the transverse aortic strip also significantly inhibited platelet aggregation induced by arachidonic acid (AA) in a volume-related manner. The inhibitory activity was decreased by the prolongation of transit time before addition of the effluent to platelet-rich plasma. Neither the inhibition of AA-induced aggregation nor the relaxation of the transverse strip by the effluent could be observed after the removal of endothelium from the aorta, or after pretreatment of aorta with mepacrine or nordihydroguaiaretic acid (NDGA). The AA-induced platelet aggregation was unaffected by pretreatment of platelets with mepacrine or NDGA at the concentration tested. Pretreatment of aorta with indomethacin failed to modify the relaxation of the transverse strip induced by the effluent. These results strongly suggest that endothelium-derived vascular relaxant factor (EDRF) possesses inhibitory activity on AA-induced aggregation in addition to its vasodilator activity.
Topics: Acetylcholine; Animals; Aorta, Thoracic; Arachidonic Acid; Arachidonic Acids; Catechols; Endothelium; In Vitro Techniques; Indomethacin; Male; Masoprocol; Perfusion; Platelet Aggregation; Quinacrine; Rabbits; Vasodilation
PubMed: 3089351
DOI: 10.1111/j.1476-5381.1986.tb10218.x -
The Journal of Biological Chemistry May 1993Bone resorption requires cooperation between osteoclasts and mononuclear accessory cells by mechanisms which have not been elucidated. Since multinucleated cells in...
Bone resorption requires cooperation between osteoclasts and mononuclear accessory cells by mechanisms which have not been elucidated. Since multinucleated cells in giant cell tumors of bone have many phenotypic and functional characteristics of normal osteoclasts, we have examined the interaction between the bone-resorbing multinucleated cells and the distinct mononuclear stromal cells from these tumors. We have found that these mononuclear cells produce an activity which stimulates both giant cells from giant cell tumors and rodent osteoclasts to resorb bone in vitro. We have identified the activity and found that it represents several products of the 5-lipoxygenase pathway of arachidonic acid metabolism, namely 5-hydroxyeicosatetraenoic acid and the leukotrienes. These data indicate that 5-lipoxygenase metabolites stimulate isolated osteoclasts to resorb bone in vitro and may represent a mechanism by which mononuclear stromal cells in human giant cell tumors communicate with the giant cells. In addition, these results may explain a possible mechanism for communication between accessory cells and osteoclasts involved in normal bone resorption.
Topics: Acid Phosphatase; Animals; Arachidonate 5-Lipoxygenase; Arachidonic Acids; Bone Matrix; Bone Resorption; Chickens; Culture Media, Conditioned; Endopeptidases; Female; Flurbiprofen; Humans; Hydroxyeicosatetraenoic Acids; Indomethacin; Leukotrienes; Lipoxygenase Inhibitors; Masoprocol; Osteoclasts; Tartrates; Ultraviolet Rays
PubMed: 8486677
DOI: No ID Found -
Shokuhin Eiseigaku Zasshi. Journal of... Jun 2005Identification and determination of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), nordihydroguaiaretic acid (NDGA), propyl gallate (PG) and...
Identification and determination of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), nordihydroguaiaretic acid (NDGA), propyl gallate (PG) and tert-butylhydroquinone (TBHQ) by means of LC/MS and GC/MS were examined. These five phenolic antioxidants were detected as their pseudo-molecular ions [M-H]- by LC/MS using a Shim-pack FC-ODS column with drying gas. Moreover, BHA, BHT and TBHQ were detected based on their mass fragment ions by GC/MS. Decomposition of TBHQ, NDGA and PG during analysis could be prevented by the addition of L-ascorbic acid (AsA) to the extraction solvent. All five antioxidants were extracted from nikuman, olive oils, peanut butter, pasta sauce and chewing gum with a mixture of acetonitrile-2-propanol-ethanol (2:1:1) containing 0.1% AsA (AsA mixture), which had been cooled in a freezer and filtered. One part filtrate and 5 parts water were mixed and placed on a Mega-Bond Elut C18 cartridge, except in the case of chewing gum. Lipids in foods were removed on a C18 cartridge by washing with 5 mL of 5% acetic acid, and antioxidants were eluted with 5 mL of AsA mixture. The antioxidants spiked into nikuman, olive oil, peanut butter, pasta sauce and chewing gum were successfully identified and their concentrations determined by LC/MS, and GC/MS with good recoveries.
Topics: Antioxidants; Ascorbic Acid; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Chromatography, Liquid; Food Analysis; Gas Chromatography-Mass Spectrometry; Hydroquinones; Masoprocol; Mass Spectrometry; Phenols; Propyl Gallate
PubMed: 16042291
DOI: 10.3358/shokueishi.46.63 -
American Journal of Physiology. Heart... Feb 2002Increased 5-lipoxygenase (5LO) expression in pulmonary artery endothelial cells (PAECs) has been observed in primary pulmonary hypertension, a disorder associated with...
Increased 5-lipoxygenase (5LO) expression in pulmonary artery endothelial cells (PAECs) has been observed in primary pulmonary hypertension, a disorder associated with pulmonary vascular remodeling and aberrant endothelial cell proliferation. To examine whether 5LO plays a role in endothelial cell proliferation, we analyzed the effect of 5LO inhibitors on cultured human PAECs. Analysis of [(3)H]thymidine incorporation showed that 5LO and 5LO-activating protein inhibitors AA-861, nordihydroguaiaretic acid (NDGA), and MK-886 all inhibited PAEC growth in a dose-dependent manner, with maximal inhibition of >90% and IC(50) values of 3.9, 1.8, and 0.48 microM, respectively. The effect of AA-861 and NDGA correlated with their effect on 5LO activity in PAECs. Concentrations of these inhibitors at or below their IC(90) values did not cause significant cell death as determined by lactate dehydrogenase release, but decreased cell doubling, as measured by cell counting at 24 h after serum replenishment. Analysis of DNA content suggested that the inhibitors led to an accumulation of PAECs at the G(0)/G(1) phase. Antisense oligonucleotides to 5LO mRNA delivered at a transfection efficiency of approximately 60% inhibited cell growth by 40 +/- 26% compared with that of a sequence-unrelated oligonucleotide. Indomethacin had no effect on PAEC growth over a range of concentrations (0.3-5 microM). These data show that 5LO inhibitors impaired the proliferative response of the cultured PAECs, suggesting that this enzyme may contribute to PAEC growth under certain pathological conditions.
Topics: Apoptosis; Arachidonate 5-Lipoxygenase; Benzoquinones; Cell Division; Cells, Cultured; Comet Assay; Cyclooxygenase Inhibitors; Endothelium, Vascular; Growth Substances; Humans; Indoles; Indomethacin; Lipoxygenase Inhibitors; Masoprocol; Oligonucleotides, Antisense; Pulmonary Artery; S Phase; Thymidine; Transfection; Tritium
PubMed: 11788406
DOI: 10.1152/ajpheart.00003.2001 -
Nordihydroguaiaretic acid potently breaks down pre-formed Alzheimer's beta-amyloid fibrils in vitro.Journal of Neurochemistry May 2002Inhibition of the accumulation of amyloid beta-peptide (Abeta) and the formation of beta-amyloid fibrils (fAbeta) from Abeta, as well as the degradation of pre-formed...
Inhibition of the accumulation of amyloid beta-peptide (Abeta) and the formation of beta-amyloid fibrils (fAbeta) from Abeta, as well as the degradation of pre-formed fAbeta in the CNS would be attractive therapeutic objectives for the treatment of Alzheimer's disease (AD). We previously reported that nordihydroguaiaretic acid (NDGA) inhibited fAbeta formation from Abeta(1-40) and Abeta(1-42) dose-dependently in the range of 10-30 micromin vitro. Utilizing fluorescence spectroscopic analysis with thioflavin T and electron microscopic study, we show here that NDGA dose-dependently breaks down fAbeta(1-40) and fAbeta(1-42) within a few hours at pH 7.5 at 37 degrees C. At 4 h, the fluorescence of fAbeta(1-40) and fAbeta(1-42) incubated with 50 microm NDGA was 5% and 10% of the initial fluorescence, respectively. The activity of NDGA to break down these fAbetas was observed even at a low concentration of 0.1 microm. At 1 h, many short, sheared fibrils were observed in the mixture incubated with 50 microm NDGA, and at 4 h, the number of fibrils reduced markedly, and small amorphous aggregates were observed. We next compared the activity of NDGA to break down fAbeta(1-40) and fAbeta(1-42), with other molecules reported to inhibit fAbeta formation from Abeta and/or to degrade pre-formed fAbeta both in vivo and in vitro. At a concentration of 50 microm, the overall activity of the molecules examined in this study was in the order of: NDGA >> rifampicin = tetracycline > poly(vinylsulfonic acid, sodium salt) = 1,3-propanedisulfonic acid, disodium salt > beta-sheet breaker peptide (iAbeta5). In cell culture experiments, fAbeta disrupted by NDGA were less toxic than intact fAbeta, as demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Although the mechanisms by which NDGA inhibits fAbeta formation from Abeta, as well as breaking down pre-formed fAbetain vitro, are still unclear, NDGA could be a key molecule for the development of therapeutics for AD.
Topics: Amyloid beta-Peptides; Benzothiazoles; Cell Line; Cell Survival; Dose-Response Relationship, Drug; Humans; Kidney; Macromolecular Substances; Masoprocol; Microscopy, Electron; Peptide Fragments; Protein Binding; Spectrometry, Fluorescence; Thiazoles
PubMed: 12065652
DOI: 10.1046/j.1471-4159.2002.00904.x -
The Journal of Biological Chemistry Mar 2004The role of endosomal acidification and retrograde transport for the uptake of the highly basic cell-penetrating peptides penetratin, Tat, and oligoarginine was...
The role of endosomal acidification and retrograde transport for the uptake of the highly basic cell-penetrating peptides penetratin, Tat, and oligoarginine was investigated. The effect of a panel of drugs that interfere with discrete steps of endocytosis or Golgi-mediated transport on uptake and cellular distribution of fluorescein-labeled peptide analogues was probed by confocal microscopy, flow cytometry, and fluorescence spectroscopy of whole cell lysates. The analyses were carried out in MC57 fibrosarcoma cells and in HeLa cells. While MC57 fibrosarcoma cells showed some vesicular fluorescence and a pronounced cytoplasmic fluorescence, in HeLa cells little cytoplasmic fluorescence was observed. In MC57 cells the inhibitors of endosomal acidification chloroquine and bafilomycin A1 abolished the release of the peptides into the cytoplasm. Release into the cytosol preserved endosomal integrity. In addition, cellular uptake of the peptides was inhibited by brefeldin A, a compound interfering with trafficking in the trans-Golgi network. In contrast, nordihydroguaiaretic acid, a drug that stimulates the rapid retrograde movement of both Golgi stacks and trans-Golgi network to the endoplasmic reticulum, promoted a cytoplasmic localization of Tat peptides in peptide-pulsed HeLa cells. The effects of these drugs on trafficking shared characteristics with those reported for the trafficking of plant and bacterial toxins, such as cholera toxin, which reach the cytoplasm by means of retrograde transport. A sequence comparison revealed a common stretch of 8-10 amino acids with high sequence homology to the Tat peptide. The structural and functional data therefore strongly suggest a common mechanism of import for cationic cell-penetrating peptides and the toxins.
Topics: Antioxidants; Biological Transport; Brefeldin A; Cations; Cell Line, Tumor; Cholera Toxin; Chromatography, High Pressure Liquid; Cytoplasm; Endocytosis; Endoplasmic Reticulum; Endosomes; Flow Cytometry; Fluorescein; Fluoresceins; Golgi Apparatus; HeLa Cells; Humans; Masoprocol; Microscopy, Confocal; Models, Biological; Peptides; Protein Binding; Protein Synthesis Inhibitors; Spectrometry, Fluorescence; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Subcellular Fractions; trans-Golgi Network
PubMed: 14707144
DOI: 10.1074/jbc.M311461200 -
Oncotarget Jan 2017Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) represent a rare and heterogenous tumor entity. Importantly, the highly proliferative subgroup of...
Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) represent a rare and heterogenous tumor entity. Importantly, the highly proliferative subgroup of neuroendocrine carcinoma (GEP-NEC) is characterized by high resistance to conventional chemotherapy. Consequently, there is an urgent need to identify novel therapeutic targets, especially for GEP-NEC. Thus, we focused on Inhibitor of apoptosis protein (IAP) family members survivin and XIAP that orchestrate inhibition of apoptosis, induce resistance against chemotherapeutics and facilitate tumor metastasis. Copy number gains (CNGs) could be detected by microarray comparative genomic hybridization for survivin and XIAP in 60 % and 26.7 % of all GEP-NENs, respectively. Immunohistochemical staining of tissue specimens from 77 consecutive patients with GEP-NEN demonstrated increased survivin protein expression levels in tissue specimens of highly proliferative GEP-NEC or GEP-NEN located in the stomach and colon. In contrast, XIAP overexpression was associated with advanced tumor stages. Knockdown of survivin and XIAP markedly reduced cell proliferation and tumor growth. In vitro, YM155 induced apoptotic cell death accompanied by a reduction in cell proliferation and inhibited GEP-NEC xenograft growth. Taken together, our data provide evidence for a biological relevance of these IAPs in GEP-NEN and support a potential role of survivin as therapeutic target especially in the subgroup of aggressive GEP-NEC.
Topics: Animals; Antineoplastic Agents; Apoptosis; Biomarkers, Tumor; Carcinoma, Neuroendocrine; Cell Line, Tumor; Cell Proliferation; Comparative Genomic Hybridization; DNA Copy Number Variations; Dose-Response Relationship, Drug; Female; Gene Dosage; Gene Expression Regulation, Neoplastic; Humans; Imidazoles; Immunohistochemistry; Inhibitor of Apoptosis Proteins; Intestinal Neoplasms; Male; Masoprocol; Mice, Inbred NOD; Mice, SCID; Molecular Targeted Therapy; Naphthoquinones; Oligonucleotide Array Sequence Analysis; Pancreatic Neoplasms; RNA Interference; Retrospective Studies; Signal Transduction; Stomach Neoplasms; Survivin; Time Factors; Transfection; Tumor Burden; X-Linked Inhibitor of Apoptosis Protein; Xenograft Model Antitumor Assays
PubMed: 28039474
DOI: 10.18632/oncotarget.14207 -
PloS One 2015Nordihydroguaiaretic acid (NDGA), the main metabolite of Creosote bush, has been shown to have profound effects on the core components of the metabolic syndrome (MetS),...
Effect of Creosote Bush-Derived NDGA on Expression of Genes Involved in Lipid Metabolism in Liver of High-Fructose Fed Rats: Relevance to NDGA Amelioration of Hypertriglyceridemia and Hepatic Steatosis.
Nordihydroguaiaretic acid (NDGA), the main metabolite of Creosote bush, has been shown to have profound effects on the core components of the metabolic syndrome (MetS), lowering blood glucose, free fatty acids (FFA) and triglyceride (TG) levels in several models of dyslipidemia, as well as improving body weight (obesity), insulin resistance, diabetes and hypertension, and ameliorating hepatic steatosis. In the present study, a high-fructose diet (HFrD) fed rat model of hypertriglyceridemia was employed to further delineate the underlying mechanism by which NDGA exerts its anti-hypertriglyceridemic action. In the HFrD treatment group, NDGA administration by oral gavage decreased plasma levels of TG, glucose, FFA, and insulin, increased hepatic mitochondrial fatty acid oxidation and attenuated hepatic TG accumulation. qRT-PCR measurements indicated that NDGA treatment increased the mRNA expression of key fatty acid transport (L-FABP, CD36), and fatty acid oxidation (ACOX1, CPT-2, and PPARα transcription factor) genes and decreased the gene expression of enzymes involved in lipogenesis (FASN, ACC1, SCD1, L-PK and ChREBP and SREBP-1c transcription factors). Western blot analysis indicated that NDGA administration upregulated hepatic insulin signaling (P-Akt), AMPK activity (P-AMPK), MLYCD, and PPARα protein levels, but decreased SCD1, ACC1 and ACC2 protein content and also inactivated ACC1 activity (increased P-ACC1). These findings suggest that NDGA ameliorates hypertriglyceridemia and hepatic steatosis primarily by interfering with lipogenesis and promoting increased channeling of fatty acids towards their oxidation.
Topics: AMP-Activated Protein Kinases; Acetyl-CoA Carboxylase; Animals; Blotting, Western; Fatty Acid-Binding Proteins; Fatty Liver; Fructose; Gene Expression Regulation; Hypertriglyceridemia; Larrea; Lipid Metabolism; Lipogenesis; Liver; Male; Masoprocol; PPAR alpha; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; Sterol Regulatory Element Binding Protein 1
PubMed: 26394137
DOI: 10.1371/journal.pone.0138203 -
Aging Cell Apr 2014Four agents--acarbose (ACA), 17-α-estradiol (EST), nordihydroguaiaretic acid (NDGA), and methylene blue (MB)--were evaluated for lifespan effects in genetically...
Four agents--acarbose (ACA), 17-α-estradiol (EST), nordihydroguaiaretic acid (NDGA), and methylene blue (MB)--were evaluated for lifespan effects in genetically heterogeneous mice tested at three sites. Acarbose increased male median lifespan by 22% (P < 0.0001), but increased female median lifespan by only 5% (P = 0.01). This sexual dimorphism in ACA lifespan effect could not be explained by differences in effects on weight. Maximum lifespan (90th percentile) increased 11% (P < 0.001) in males and 9% (P = 0.001) in females. EST increased male median lifespan by 12% (P = 0.002), but did not lead to a significant effect on maximum lifespan. The benefits of EST were much stronger at one test site than at the other two and were not explained by effects on body weight. EST did not alter female lifespan. NDGA increased male median lifespan by 8-10% at three different doses, with P-values ranging from 0.04 to 0.005. Females did not show a lifespan benefit from NDGA, even at a dose that produced blood levels similar to those in males, which did show a strong lifespan benefit. MB did not alter median lifespan of males or females, but did produce a small, statistically significant (6%, P = 0.004) increase in female maximum lifespan. These results provide new pharmacological models for exploring processes that regulate the timing of aging and late-life diseases, and in particular for testing hypotheses about sexual dimorphism in aging and health.
Topics: Acarbose; Animals; Biomarkers; Body Weight; Estradiol; Female; Longevity; Male; Masoprocol; Methylene Blue; Mice; Survival Analysis
PubMed: 24245565
DOI: 10.1111/acel.12170 -
Immunology Nov 1985The action of pharmacologic agents on chymase-induced exocytosis of beta-hexosaminidase and arachidonic acid (AA) metabolism by rat serosal mast cells (RSMC) was...
The action of pharmacologic agents on chymase-induced exocytosis of beta-hexosaminidase and arachidonic acid (AA) metabolism by rat serosal mast cells (RSMC) was determined and compared with their effects on anti-IgE induced activation. Indomethacin (INDO) (less than or equal to 10 microM), a cyclooxygenase inhibitor, did not affect chymase- or anti-IgE-mediated exocytosis, while completely inhibiting prostaglandin D2 (PGD2) release at 1.25 microM. Theophylline (THEO), mepacrine, 3-amino-1-[m-(trifluoromethyl)-phenyl]-2-pyrazoline (BW755C), and diethylcarbamazine (DEC), inhibitors of adenosine binding and phosphodiesterases, phospholipases, AA metabolism, and vesicular transport as well as leukotriene A4 formation, respectively, inhibited exocytosis with ID50 values of 3.4, 0.22, 3.4 and 1.9 mM for chymase and 2.4, 0.17, 2.8 and 5.2 mM for anti-IgE. These agents inhibited net PGD2 release with ID50 values of 2.1, 0.04, less than 0.05, and 1.5 mM for chymase and of 0.5, 0.1, less than 0.05, and 4 mM for anti-IgE. 5,6-Dehydroarachidonic acid (DHA) and arachidonyl hydroxylamine (AH), 5-lipoxygenase inhibitors, did not affect chymase-mediated exocytosis; anti-IgE-mediated exocytosis was not altered by AH but was suppressed by DHA (ID50 = 20 microM). Nordihydroguaiaretic acid (NDGA), an antioxidant, inhibited chymase-mediated exocytosis dose-dependently (ID50 less than or equal to 13.3 microM) while decreasing anti-IgE-mediated exocytosis by only 30% at 2.5-20 microM; net PGD2 release induced by both stimuli was inhibited dose-dependently. 2',5'-Dideoxyadenosine (DDA) and 1,6-di(0-(carbamoyl)cyclohexanone oxime)hexane (RHC 80267) and inhibitors of adenylate cyclase and of di-triglyceride lipases, respectively, had little effect on exocytosis induced by chymase but inhibited that induced by anti-IgE with ID50 values of 0.4 mM and 37 microM, respectively. With DDA the inhibition of net PGD2 release occurred with anti-IgE but not chymase, whereas RHC 80267 inhibited both chymase and anti-IgE-mediated PGD2 release. Differential inhibition of activation-secretion suggests either that chymase provides a step inhibited in IgE-mediated exocytosis by DDA, RHC 80267 and DHA, or that the activating pathway initiated by chymase is distinct.
Topics: 4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine; Animals; Arachidonic Acids; Catechols; Chymases; Deoxyadenosines; Dideoxyadenosine; Diethylcarbamazine; Dose-Response Relationship, Drug; Endopeptidases; Exocytosis; Hexosaminidases; Immunoglobulin E; In Vitro Techniques; Indomethacin; Masoprocol; Mast Cells; Prostaglandin D2; Prostaglandins D; Pyrazoles; Quinacrine; Rats; Rats, Inbred Strains; Serine Endopeptidases; Theophylline
PubMed: 3935569
DOI: No ID Found