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Medical Science Monitor : International... Nov 2011HIV infection and treatment with highly active antiretroviral therapy (HAART) including HIV protease inhibitor ritonavir (RTV) have been associated with endothelial...
BACKGROUND
HIV infection and treatment with highly active antiretroviral therapy (HAART) including HIV protease inhibitor ritonavir (RTV) have been associated with endothelial dysfunction and cardiovascular disease including pulmonary arterial hypertension. The objective of this study was to determine if nordihydroguaiaretic acid (NDGA), a natural herbal antioxidant found in the creosote bush Larrea tridentate, can protect vascular tissues against RTV-induced vascular injury.
MATERIAL/METHODS
Fresh porcine pulmonary artery (PA) rings were treated with a clinically relevant concentration of RTV (15 µmol/L) with or without NDGA for 24 hours, and then subjected to myograph analysis for vasomotor reactivity. Expression of endothelial nitric oxide synthase (eNOS) in both treated PA rings and human pulmonary artery endothelial cells (HPAECs) was analyzed by real-time PCR and immunohistochemistry. Oxidative stress levels were analyzed with the lucigenin-enhanced chemiluminescence and glutathione assay.
RESULTS
In response to bradykinin at 10-10 mol/L, RTV-treated PA rings showed a 39% reduction in endothelium-dependent vasorelaxation compared with the control vessels (P<0.05); when co-cultured with NDGA (1.75 or 3.50 µmol/L), the relaxation increased by 25% and 48%, respectively. RTV also decreased the maximal contraction and endothelium-independent vasorelaxation in RTV-treated vessels, while NDGA improved these vasomotor responses. In addition, treatment of RTV significantly decreased eNOS mRNA levels in both porcine PAs and HPAECs, and reduced eNOS immunoreactivity in porcine PAs, while NDGA significantly inhibited this effect of RTV. Furthermore, NDGA significantly blocked RTV-induced increase of superoxide anion in the PA rings and inhibited RTV-induced decrease of glutathione in HPAECs.
CONCLUSIONS
NDGA effectively inhibits the detrimental effects of HIV protease inhibitor RTV on vasomotor functions in porcine PAs. NDGA also blocks RTV-induced decrease of eNOS expression and increase of oxidative stress in both porcine PAs and HPAECs. This study may provide valuable information for the development of effective strategies for the prevention and treatment of HAART-associated cardiovascular complications.
Topics: Animals; Antioxidants; Electromyography; Endothelium, Vascular; HIV Infections; HIV Protease Inhibitors; Immunohistochemistry; Larrea; Masoprocol; Nitric Oxide Synthase Type III; Oxidative Stress; Peripheral Vascular Diseases; Real-Time Polymerase Chain Reaction; Ritonavir; Swine; Vasodilation
PubMed: 22037733
DOI: 10.12659/msm.882040 -
The Journal of Biological Chemistry Nov 1996We have previously reported that hydrogen peroxide, an active oxygen species and a cellular oxidant, induces c-Fos and c-Jun mRNA expression and DNA synthesis in...
We have previously reported that hydrogen peroxide, an active oxygen species and a cellular oxidant, induces c-Fos and c-Jun mRNA expression and DNA synthesis in vascular smooth muscle cells and that these events require arachidonic acid release and metabolism through the lipoxygenase pathway. Here we have identified the eicosanoids that mediate the hydrogen peroxide-induced growth-related events in these cells. Hydrogen peroxide stimulated the production of 12- and 15-hydroperoxyeicosatetraenoic acids in vascular smooth muscle cells. Both 12- and 15-hydroperoxyeicosatetraenoic acids induced the expression of c-Fos and c-Jun protein and increased activating protein 1 (AP-1) activity, as measured by AP-1-DNA binding and AP-1-dependent human collagenase promoter-driven chloramphenicol acetyltransferase reporter gene transcription. Hydrogen peroxide and arachidonic acid also induced the expression of c-Fos and c-Jun protein and AP-1 activity. Nordihydroguaiaretic acid, an inhibitor of the lipoxygenase pathway, significantly inhibited both hydrogen peroxide and arachidonic acid-stimulated c-Fos and c-Jun protein expression and AP-1 activity. Together, these findings suggest that hydrogen peroxide induces the production of eicosanoids and that the eicosanoids are potential mediators of the oxidative stress-stimulated growth-related events in vascular smooth muscle cells.
Topics: Animals; Aorta, Thoracic; Arachidonic Acid; Cells, Cultured; Chloramphenicol O-Acetyltransferase; Collagenases; Gene Expression; Genes, Reporter; Humans; Hydrogen Peroxide; Leukotrienes; Lipid Peroxides; Male; Masoprocol; Muscle, Smooth, Vascular; Oxidative Stress; Promoter Regions, Genetic; Proto-Oncogene Proteins c-fos; Proto-Oncogene Proteins c-jun; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Transcription Factor AP-1; Transcription, Genetic; Transfection
PubMed: 8910370
DOI: 10.1074/jbc.271.44.27760 -
Biochemistry and Cell Biology =... Apr 20124-(Hydroxyphenyl)retinamide (4-HPR) is a synthetic retinoid with a strong apoptotic effect towards different cancer cell lines in vitro, and it is currently tested in...
4-(Hydroxyphenyl)retinamide (4-HPR) is a synthetic retinoid with a strong apoptotic effect towards different cancer cell lines in vitro, and it is currently tested in clinical trials. Increases of reactive oxygen species (ROS) and modulation of endogenous sphingolipid levels are well-described events observed upon 4-HPR treatment, but there is still a lack of understanding of their relationship and their contribution to cell death. LC-MS analysis of sphingolipids revealed that in human leukemia CCRF-CEM and Jurkat cells, 4-HPR induced dihydroceramide but not ceramide accumulation even at sublethal concentrations. Myriocin prevented the 4-HPR-induced dihydroceramide accumulation, but it did not prevent the loss of viability and increase of intracellular ROS production. On the other hand, ascorbic acid, Trolox, and vitamin E reversed 4-HPR effects on cell death but not dihydroceramide accumulation. NDGA, described as a lipoxygenase inhibitor, exerted a significantly higher antioxidant activity than vitamin E and abrogated 4-HPR-mediated ROS. It did not however rescue cellular viability. Taken together, this study demonstrates that early changes observed upon 4-HPR treatment, i.e., sphingolipid modulation and ROS production, are mechanistically independent events. Furthermore, the results indicate that 4-HPR-driven cell death may occur even in the absence of dihydroceramide or ROS accumulation. These observations should be taken into account for an improved design of drug combinations.
Topics: Antineoplastic Agents; Antioxidants; Apoptosis; Ascorbic Acid; Cell Line, Tumor; Cell Survival; Ceramides; Fenretinide; Flavanones; Humans; Leukemia; Lipid Peroxidation; Lipoxygenase Inhibitors; Masoprocol; Mitochondria; Oxidative Stress; Oxidoreductases; Reactive Oxygen Species; Sphingolipids; Vitamin E
PubMed: 22428532
DOI: 10.1139/o2012-001 -
British Journal of Cancer Apr 2002Lipoxygenase metabolites of arachidonic acid can act as growth promoting factors for various cancer cell lines. Here we demonstrate that the 5-lipoxygenase inhibitor...
Lipoxygenase metabolites of arachidonic acid can act as growth promoting factors for various cancer cell lines. Here we demonstrate that the 5-lipoxygenase inhibitor nordihydroguaiaretic acid potently inhibits anchorage-independent growth of human pancreatic and cervical cancer cells in soft agar and delays growth of pancreatic and cervical tumours established in athymic mice. Furthermore, nordihydroguaiaretic acid induces apoptosis of these cancer cells in vitro and in vivo. Potential mechanisms mediating these effects of nordihydroguaiaretic acid were examined. Nordihydroguaiaretic acid had no inhibitory effect on growth and survival signals such as tyrosine phosphorylation of the epidermal growth factor receptor or basal and growth factor-stimulated activities of extracellular signal-regulated kinase 1/2, p70(s6k) and AKT but selectively inhibited expression of cyclin D1 in the cancer cells. In addition, treatment with nordihydroguaiaretic acid lead to a disruption of the filamentous actin cytoskeleton in human pancreatic and cervical cancer cells which was accompanied by the activation of Jun-NH(2)-terminal kinase and p38(mapk). Similar effects were obtained by treatment of the cancer cells with cytochalasin D. These results suggest that nordihydroguaiaretic acid induces anoikis-like apoptosis as a result of disruption of the actin cytoskeleton in association with the activation of stress activated protein kinases. In conclusion, nordihydroguaiaretic acid could constitute a lead compound in the development of novel therapeutic agents for various types of cancer.
Topics: Actins; Animals; Apoptosis; Blotting, Western; Cell Adhesion; Cell Division; Cytoskeleton; Female; Humans; Lipoxygenase Inhibitors; Masoprocol; Mice; Pancreatic Neoplasms; Protein Kinases; Transplantation, Heterologous; Tumor Cells, Cultured; Uterine Cervical Neoplasms
PubMed: 11953870
DOI: 10.1038/sj.bjc.6600186 -
Laboratory Investigation; a Journal of... Dec 2012Nordihydroguaiaretic acid (NDGA) is known to have prominent anticancer activity against several cancers, and is also known to be an inhibitor of 5-lipoxygenase (5-LO)....
Nordihydroguaiaretic acid (NDGA) is known to have prominent anticancer activity against several cancers, and is also known to be an inhibitor of 5-lipoxygenase (5-LO). In this study, we investigated the regulatory function of NDGA on inflammatory bone destruction mediated by osteoclasts. NDGA markedly inhibited receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced formation of osteoclasts in cultures of murine osteoclast precursor cell line RAW-D cells and primary bone marrow-derived macrophages culture systems. The inhibitory effect of NDGA on osteoclastogenesis did not arise from the inhibition of 5-LO activity. NDGA did not affect MAPKs, such as p38, JNK, and NF-κB, but significantly inhibited the induction of NFATc1, a key transcription factor for osteoclastogenesis. NDGA also suppressed activation of ERK in osteoclast precursors. RANKL-induced calcium oscillation observed in osteoclast precursors was completely diminished by the addition of NDGA. In mature osteoclasts, RANKL-induced nuclear translocation of NFATc1 was clearly inhibited by NDGA treatment. Finally, in vivo studies demonstrated that administration of NDGA significantly reduced severe bone destruction and osteoclast recruitment in the ankle joint of rats with adjuvant-induced arthritis. These results indicate the potential utility of NDGA as a therapeutic agent for ameliorating inflammatory bone destruction in rheumatoid arthritis.
Topics: Animals; Arthritis, Experimental; Bone Resorption; Calcium Signaling; Cell Differentiation; Cell Line; Dose-Response Relationship, Drug; Female; Male; Masoprocol; Mice; Mice, Inbred C57BL; NFATC Transcription Factors; Osteitis; Osteoclasts; RANK Ligand; Rats; Rats, Sprague-Dawley
PubMed: 23044922
DOI: 10.1038/labinvest.2012.134 -
Plant Physiology Sep 2002Saturated and unsaturated N-acylethanolamines (NAEs) occur in desiccated seeds primarily as 16C and 18C species with N-palmitoylethanolamine and N-linoleoylethanolamine...
Saturated and unsaturated N-acylethanolamines (NAEs) occur in desiccated seeds primarily as 16C and 18C species with N-palmitoylethanolamine and N-linoleoylethanolamine (NAE 18:2) being most abundant. Here, we examined the metabolic fate of NAEs in vitro and in vivo in imbibed cotton (Gossypium hirsutum) seeds. When synthetic [1-(14)C]N-palmitoylethanolamine was used as a substrate, free fatty acids (FFA) were produced by extracts of imbibed cottonseeds. When synthetic [1-(14)C]NAE 18:2 was used as a substrate, FFA and an additional lipid product(s) were formed. On the basis of polarity, we presumed that the unidentified lipid was a product of the lipoxygenase (LOX) pathway and that inclusion of the characteristic LOX inhibitors nordihydroguaiaretic acid and eicosatetraynoic acid reduced its formation in vitro and in vivo. The conversion of NAE 18:2 in imbibed cottonseed extracts to 12-oxo-13-hydroxy-N-(9Z)-octadecanoylethanolamine was confirmed by gas chromatography-mass spectrometry, indicating the presence of 13-LOX and 13-allene oxide synthase, which metabolized NAE 18:2. Cell fractionation studies showed that the NAE amidohydrolase, responsible for FFA production, was associated mostly with microsomes, whereas LOX, responsible for NAE 18:2-oxylipin production, was distributed in cytosol-enriched fractions and microsomes. The highest activity toward NAE by amidohydrolase was observed 4 to 8 h after imbibition and by LOX 8 h after imbibition. Our results collectively indicate that two pathways exist for NAE metabolism during seed imbibition: one to hydrolyze NAEs in a manner similar to the inactivation of endocannabinoid mediators in animal systems and the other to form novel NAE-derived oxylipins. The rapid depletion of NAEs by these pathways continues to point to a role for NAE metabolites in seed germination.
Topics: 5,8,11,14-Eicosatetraynoic Acid; Amides; Amidohydrolases; Biological Transport; Cannabinoid Receptor Modulators; Carbon Radioisotopes; Endocannabinoids; Ethanolamines; Fatty Acids; Germination; Gossypium; Lipoxygenase; Lipoxygenase Inhibitors; Masoprocol; Palmitic Acids; Seeds
PubMed: 12226518
DOI: 10.1104/pp.004689 -
Sheng Li Xue Bao : [Acta Physiologica... Apr 2010The aim of the present study is to investigate the role of nordihydroguaiaretic acid (NDGA) on inflammatory cells accumulation after focal cerebral ischemia and the...
The aim of the present study is to investigate the role of nordihydroguaiaretic acid (NDGA) on inflammatory cells accumulation after focal cerebral ischemia and the underlying mechanism. Focal cerebral ischemia was induced by 30 min of middle cerebral artery occlusion (MCAO) followed by 72 h of reperfusion. NDGA (5 and 10 mg/kg) was administered intraperitoneally 30 min, 2, 24, 48 h after reperfusion, respectively. The brain injuries were observed by neurological and histological examination. Endogenous IgG exudation, neutrophils and macrophages/microglia accumulation, and intercellular adhesion molecule-1 (ICAM-1) protein expression were determined by immunohistochemistry 72 h after reperfusion. ICAM-1 mRNA was determined by RT-PCR 72 h after reperfusion. The catalysates of 5-lipoxygenase (5-LOX), leukotriene B4 (LTB4) and cysteinyl leukotrienes (CysLTs), were evaluated by ELISA 3 h after reperfusion. The results showed that NDGA ameliorated neurological dysfunction, decreased infarct volume, and inhibited endogenous IgG exudation, neutrophils infiltration, ICAM-1 mRNA and protein expression 72 h after reperfusion. Moreover, NDGA reduced the levels of LTB4 and CysLTs 3 h after reperfusion. However, NDGA did not reduce the accumulation of macrophages/microglia 72 h after reperfusion. These results suggest that NDGA decreases neutrophil infiltration in the subacute phase of focal cerebral ischemia via inhibiting 5-LOX activation.
Topics: Animals; Arachidonate 5-Lipoxygenase; Brain Ischemia; Immunoglobulin G; Inflammation; Intercellular Adhesion Molecule-1; Leukotriene B4; Lipoxygenase Inhibitors; Male; Masoprocol; Neutrophils; RNA, Messenger; Rats; Rats, Sprague-Dawley; Reperfusion Injury
PubMed: 20401443
DOI: No ID Found -
Journal of Lipid Research Jan 1991We have studied the generation of volatile hydrocarbons by fatty acid-modified L1210 leukemia cells in tissue culture as a measure of lipid peroxidation. There was...
We have studied the generation of volatile hydrocarbons by fatty acid-modified L1210 leukemia cells in tissue culture as a measure of lipid peroxidation. There was considerable generation of ethane, and this was dependent on cell number and Fe2+ concentration; it was eliminated by antioxidants and augmented by ascorbic acid. The assay was sensitive and reproducible; ethane was detected when as little as 0.03% of the cellular n-3 (omega-3) fatty acids were peroxidized. To gain further understanding we used a lipid modification model that allows study of cells enriched with fatty acids of different degrees of unsaturation. The quantity of ethane generated was greatest by cells modified with fatty acids of the n-3 family, and there was a high direct correlation of percentage of n-3 fatty acids contained in cellular lipids with peroxidation as measured by ethane generation. Ethane generation was more sensitive in detecting peroxidation than loss of polyunsaturated fatty acids. We conclude that lipid-supplemented leukemic cells produce ethane, and that the rate of generation is a sensitive, quantitative, and highly useful measure of lipid peroxidation when small amounts of iron are present.
Topics: Animals; Antioxidants; Cell Membrane; Ethane; Fats, Unsaturated; Fish Oils; Ibuprofen; Iron; Kinetics; Lipid Peroxidation; Malondialdehyde; Masoprocol; Mice; Tumor Cells, Cultured
PubMed: 2010696
DOI: No ID Found -
Kidney International Jun 1986The influence of environment on renal cyst growth was assessed in experiments utilizing 56 germ-free and 32 conventional male Sprague-Dawley rats fed 2%...
The influence of environment on renal cyst growth was assessed in experiments utilizing 56 germ-free and 32 conventional male Sprague-Dawley rats fed 2% nordihydroguaiaretic acid (NDGA). Among three groups of six germ-free rats allowed ad lib intake of NDGA for six weeks and deconditioned (placed into the ambient laboratory environment) at the start, at the midpoint, or not at all, cyst formation and interstitial changes (both severe) were noted only among animals deconditioned at the midpoint. Among 14 germ-free rats that were offered 0.4 g NDGA daily, deconditioned after two weeks, and sacrificed 0 to 15 days thereafter, nephron dilation and thymidine uptake by renal tubular epithelium appeared within one to three days and correlated in magnitude with each other and with the duration of the contamination interval. Deconditioning, a prior period of four or more days of exposure to NDGA in the germ-free state, the duration of the contamination period, and the presence of cecal flora were identified as prerequisites to accelerated cyst formation in this model, while the dose of ingested NDGA, the presence of bacteria within the kidney, an action of bacteria on NDGA within the colon, and the type(s) of organisms colonizing the host were not. These findings provide experimental evidence that environmental circumstance can modulate the expression of renal cystic disease.
Topics: Animals; Catechols; Cell Cycle; Energy Intake; Environment; Germ-Free Life; Kidney Diseases, Cystic; Male; Masoprocol; Microscopy, Electron, Scanning; Rats
PubMed: 3747328
DOI: 10.1038/ki.1986.116 -
Hypertension Research : Official... Feb 2003In cultured vascular smooth muscle cells (VSMCs), interleukin-1beta (IL-1beta) stimulates inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO)...
In cultured vascular smooth muscle cells (VSMCs), interleukin-1beta (IL-1beta) stimulates inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) production. IL-1beta also activates phospholipase A2 (PLA2), and induces lipoxygenase (LOX) and cyclooxygenase-2 (COX-2). The present study investigated whether these metabolites are involved in the regulation of IL-1beta-induced NO production and iNOS expression. Pretreatment with ONO-RS-082, the secretory PLA2 (sPLA2) inhibitor, at 1 to 10 micromol/l reduced IL-1beta-stimulated nitrite production and iNOS expression. Nordihydroguaiaretic acid (NDGA, 1 to 10 micromol/l), the LOX inhibitor, also reduced IL-1beta (10 ng/ml)-stimulated nitrite production and iNOS expression in a dose-dependent manner. Exogenous 12(S)-hydroxyeicosatetraenoic acids (HETE) enhanced the IL-1beta-stimulated nitrite production and iNOS expression. On the other hand, the COX inhibitors, indomethacin and NS-398, had little effect on nitrite production or iNOS expression. These results suggest that LOX products play important roles in the regulation of stimulus-induced NO production in VSMCs.
Topics: Aminobenzoates; Animals; Aorta, Thoracic; Cells, Cultured; Chlorobenzoates; Cinnamates; Cyclooxygenase Inhibitors; Flavanones; Flavonoids; Group II Phospholipases A2; Interleukin-1; Lipoxygenase; Lipoxygenase Inhibitors; Male; Masoprocol; Muscle, Smooth, Vascular; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Phosphodiesterase Inhibitors; Phospholipases A; Phospholipases A2; Rats; Rats, Wistar; ortho-Aminobenzoates
PubMed: 12627879
DOI: 10.1291/hypres.26.177