13-hydroxy-9-11-octadecadienoic-acid and Hyperplasia

Pioglitazone (PGZ), a synthetic peroxisome proliferator-activated receptor gamma (PPARγ) ligand, is known to have anti-tumor activity by inducing tumor cell apoptosis. However, it is unknown whether it can be used to prevent smoking carcinogen-induced lung tumor development. We induced mouse lung tumors using smoking carcinogen 4- methylnitrosamino-l-3-pyridyl-butanone (NNK). PGZ was given at two early stages before the tumor formation. The role and the functional mechanism of PGZ were investigated in the development of mouse pulmonary tumors. The tumor development was monitored and PPARγ activity and endogenous PPARγ ligands 15(S)-HETE, 13(S)-HODE were determined. The application of PGZ before alveolar hyperplasia formation (Group NPa) and at the early phase of alveolar hyperplasia formation (Group NPb) significantly prevented the lung tumor development especially in Group NPb mice (all p < 0.05). PGZ not only prevented the NNK-mediated reduction of endogenous ligands 15(S)-HETE and 13(S)-HODE, but also increased 13(S)-HODE level in Group NPb mice. PPARγ transcriptional activity was increased in NNKstimulated lung tissues when PGZ was given. The in vivo results were confirmed in the human lung cancer cells, which showed that PGZ induced lung cancer cell apoptosis through up-regulating nuclear PPARγ expression, inducing PPARγ transcriptional activity and increasing the levels of PPARγ ligands in NNK-treated cells. The early application of PGZ is able to prevent NNK-induced lung tumor development through maintaining the level of endogenous PPARγ ligands 15(S)-HETE and 13(S)-HODE and activation of PPARγ.

Topics: Animals; Anticarcinogenic Agents; Apoptosis; Cell Line, Tumor; Cell Proliferation; Cell Transformation, Neoplastic; Gene Expression Regulation, Neoplastic; Humans; Hydroxyeicosatetraenoic Acids; Hyperplasia; Ligands; Linoleic Acids; Lung Neoplasms; Mice; Nitrosamines; Pioglitazone; PPAR gamma; Pulmonary Alveoli; Smoking; Thiazolidinediones; Time Factors; Transcription, Genetic

We showed recently that IL-4 causes mitochondrial dysfunction in allergic asthma. IL-4 is also known to induce 12/15-lipoxygenase (12/15-LOX), a potent candidate molecule in asthma. Because vitamin E (Vit-E) reduces IL-4 and inhibits 12/15-LOX in vitro, here we tested the hypothesis that Vit-E may be effective in restoring key mitochondrial dysfunctions, thus alleviating asthma features in an experimental allergic murine model. Ovalbumin (OVA)-sensitized and challenged male BALB/c mice showed the characteristic features of asthma such as airway hyperresponsiveness (AHR), airway inflammation, and airway remodeling. In addition, these mice showed increase in the expression and metabolites of 12/15-LOX, reduction in the activity and expression of the third subunit of mitochondrial cytochrome-c oxidase, and increased cytochrome c in lung cytosol, which indicate that OVA sensitization and challenge causes mitochondrial dysfunction. Vit-E was administered orally to these mice, and 12/15-LOX expression, key mitochondrial functions, ultrastructural changes of mitochondria in bronchial epithelia, and asthmatic parameters were determined. Vit-E treatment reduced AHR, Th2 response including IL-4, IL-5, IL-13, and OVA-specific IgE, eotaxin, transforming growth factor-beta1, airway inflammation, expression and metabolites of 12/15-LOX in lung cytosol, lipid peroxidation, and nitric oxide metabolites in the lung, restored the activity and expression of the third subunit of cytochrome-c oxidase in lung mitochondria and bronchial epithelia, respectively, reduced the appearance of cytochrome c in lung cytosol, and also restored mitochondrial ultrastructural changes of bronchial epithelia. In summary, these findings show that Vit-E reduces key mitochondrial dysfunctions and alleviates asthmatic features.

Topics: 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; Airway Remodeling; Animals; Anti-Asthmatic Agents; Arachidonate 12-Lipoxygenase; Arachidonate 15-Lipoxygenase; Asthma; Bronchial Hyperreactivity; Bronchial Provocation Tests; Cytochromes c; Disease Models, Animal; Electron Transport Complex IV; Goblet Cells; Hyperplasia; Hypersensitivity; Immunoglobulin E; Interleukin-13; Interleukin-4; Interleukin-5; Linoleic Acids; Lung; Male; Mice; Mice, Inbred BALB C; Mitochondria; Ovalbumin; Oxidative Stress; Pulmonary Fibrosis; Transforming Growth Factor beta1; Vitamin E

Topics: Animals; Cell Division; Cell Membrane; Cytosol; Diglycerides; Epidermis; Guinea Pigs; Hyperplasia; Isoenzymes; Linoleic Acids; Protein Kinase C; Protein Kinase C beta; Protein Kinase C-alpha

A method for determination of the lipoxygenase products of linoleic acid (9- and 13-hydroxyoctadecadienoic acid; 9-HODE, 13-HODE) and of arachidonic acid (5-, 8-, 9-, 11-, 12-, and 15-hydroxyeicosatetraenoic acid; 5-, 8-, 9-, 11-, 12-, and 15-HETE) is described. The method combines solid-phase extraction, derivatization to the corresponding fully hydrogenated methylester/trimethylsilylether derivatives and capillary gas chromatography coupled with electron impact mass spectrometry. Each regioisomeric HODE and HETE shows a unique pair of mass spectrometric fragment ions originating from fission of the fatty acid carbon chain at the hydroxylated position. The carboxyl-terminal fragment is used for quantification relative to a carboxyl-18O2-labeled analogue added as internal standard and the methyl-terminal fragment is monitored for confirmation. The assay can be extended for quantification of the complete hydroxylation profile of linoleic and arachidonic acid. Applications of this assay are demonstrated for the quantification of HODEs and HETEs in normal, hyperplastic, and neoplastic mouse epidermis. In mouse epidermis papilloma, the tissue levels of 8- and 12-HETE were found to be increased by one to two orders of magnitude compared to levels in normal epidermis.

Topics: Animals; Arachidonic Acids; Female; Gas Chromatography-Mass Spectrometry; Hydroxyeicosatetraenoic Acids; Hydroxylation; Hyperplasia; Linoleic Acids; Linoleic Acids, Conjugated; Lipoxygenase; Mice; Papilloma; Skin; Skin Neoplasms