13-hydroxy-9-11-octadecadienoic-acid and Disease-Models--Animal

Nonalcoholic fatty liver disease (NAFLD) is becoming a major public health problem worldwide. The study aimed to evaluate the concentration of eicosanoids in serum and liver tissue during steatosis progression and to assess whether eicosanoid change scores may predict liver tissue remodeling. Thirty six eight-week-old male Sprague Dawley rats were enrolled and sacrificed at different stages of NAFLD. Eicosanoid concentrations, namely lipoxin A

Topics: Animals; Biomarkers; Chromatography, Liquid; Dinoprostone; Disease Models, Animal; Disease Progression; Docosahexaenoic Acids; Eicosanoids; Eicosapentaenoic Acid; Hydroxyeicosatetraenoic Acids; Linoleic Acids; Lipoxins; Liver; Male; Non-alcoholic Fatty Liver Disease; Rats; Rats, Sprague-Dawley

A global nontargeted longitudinal metabolomics study was carried out in male and female NOD mice to characterize the time-profile of the changes in the metabolic signature caused by onset of type 1 diabetes (T1D) and identify possible early biomarkers in T1D progressors. Metabolomics profiling of samples collected at five different time-points identified 676 and 706 biochemicals in blood and feces, respectively. Several metabolites were expressed at significantly different levels in progressors at all time-points, and their proportion increased strongly following onset of hyperglycemia. At the last time-point, when all progressors were diabetic, a large percentage of metabolites had significantly different levels: 57.8% in blood and 27.8% in feces. Metabolic pathways most strongly affected included the carbohydrate, lipid, branched-chain amino acid, and oxidative ones. Several biochemicals showed considerable (>4×) change. Maltose, 3-hydroxybutyric acid, and kojibiose increased, while 1,5-anhydroglucitol decreased more than 10-fold. At the earliest time-point (6-week), differences between the metabolic signatures of progressors and nonprogressors were relatively modest. Nevertheless, several compounds had significantly different levels and show promise as possible early T1D biomarkers. They include fatty acid phosphocholine derivatives from the phosphatidylcholine subpathway (elevated in both blood and feces) as well as serotonin, ribose, and arabinose (increased) in blood plus 13-HODE, tocopherol (increased), diaminopimelate, valerate, hydroxymethylpyrimidine, and dulcitol (decreased) in feces. A combined metabolic signature based on these compounds might serve as an early predictor of T1D-progressors.

Topics: Age of Onset; Amino Acids; Animals; Biomarkers; Carbohydrates; Diabetes Mellitus, Type 1; Disease Models, Animal; Feces; Humans; Linoleic Acids; Lipids; Metabolic Networks and Pathways; Metabolome; Metabolomics; Mice; Mice, Inbred NOD; Tocopherols

Chronic alcohol feeding causes lipid accumulation and apoptosis in the liver. This study investigated the role of bioactive lipid metabolites in alcohol-induced liver damage and tested the potential of targeting arachidonate 15-lipoxygenase (ALOX15) in treating alcoholic liver disease (ALD). Results showed that chronic alcohol exposure induced hepatocyte apoptosis in association with increased hepatic 13-HODE. Exposure of 13-HODE to Hepa-1c1c7 cells induced oxidative stress, ER stress and apoptosis. 13-HODE also perturbed proteins related to lipid metabolism. HODE-generating ALOX15 was up-regulated by chronic alcohol exposure. Linoleic acid, but not ethanol or acetaldehyde, induced ALOX15 expression in Hepa-1c1c7 cells. ALOX15 knockout prevented alcohol-induced liver damage via attenuation of oxidative stress, ER stress, lipid metabolic disorder, and cell death signaling. ALOX15 inhibitor (PD146176) treatment also significantly alleviated alcohol-induced oxidative stress, lipid accumulation and liver damage. These results demonstrated that activation of ALOX15/13-HODE circuit critically mediates the pathogenesis of ALD. This study suggests that ALOX15 is a potential molecular target for treatment of ALD.

Topics: Alcohols; Animals; Apoptosis; Arachidonate 12-Lipoxygenase; Arachidonate 15-Lipoxygenase; Disease Models, Animal; Hepatocytes; Linoleic Acids; Liver Diseases, Alcoholic; Mice; Up-Regulation

Alcoholic liver disease is a major human health problem leading to significant morbidity and mortality in the United States and worldwide. Dietary fat plays an important role in alcoholic liver disease pathogenesis. Herein, we tested the hypothesis that a combination of ethanol and a diet rich in linoleic acid (LA) leads to the increased production of oxidized LA metabolites (OXLAMs), specifically 9- and 13-hydroxyoctadecadienoic acids (HODEs), which contribute to a hepatic proinflammatory response exacerbating liver injury. Mice were fed unsaturated (with a high LA content) or saturated fat diets (USF and SF, respectively) with or without ethanol for 10 days, followed by a single binge of ethanol. Compared to SF+ethanol, mice fed USF+ethanol had elevated plasma alanine transaminase levels, enhanced hepatic steatosis, oxidative stress, and inflammation. Plasma and liver levels of 9- and 13-HODEs were increased in response to USF+ethanol feeding. We demonstrated that primarily 9-HODE, but not 13-HODE, induced the expression of several proinflammatory cytokines in vitro in RAW264.7 macrophages. Finally, deficiency of arachidonate 15-lipoxygenase, a major enzyme involved in LA oxidation and OXLAM production, attenuated liver injury and inflammation caused by USF+ethanol feeding but had no effect on hepatic steatosis. This study demonstrates that OXLAM-mediated induction of a proinflammatory response in macrophages is one of the potential mechanisms underlying the progression from alcohol-induced steatosis to alcoholic steatohepatitis.

Topics: Animals; Arachidonate 15-Lipoxygenase; Binge Drinking; Body Composition; Cytokines; Dietary Fats; Disease Models, Animal; Ethanol; Inflammation; Linoleic Acid; Linoleic Acids; Linoleic Acids, Conjugated; Liver; Macrophages; Metabolome; Mice; Mice, Inbred C57BL; Oxidation-Reduction; Oxidative Stress; RAW 264.7 Cells

Psoriasis is a chronic, debilitating skin condition that affects approximately 125 million individuals worldwide. The cause of psoriasis appears multifactorial, and no unified mitigating signal or single antigenic target has been identified to date. Metabolomic studies hold great potential for explaining disease mechanism, facilitating early diagnosis, and identifying potential therapeutic areas. Here, we present an integrated disease metabolomic biomarker discovery strategy that combines mechanism-based biomarker discovery with clinical sample-based metabolomic profiling. We applied this strategy in identifying and understanding metabolite biomarkers for psoriasis. The key innovation of our strategy is a novel mechanism-based metabolite prediction system, mmPredict, which assimilates vast amounts of existing knowledge of diseases and metabolites. mmPredict first constructed a psoriasis-specific mouse mutational phenotype profile. It then constructed phenotype profiles for a total of 259,170 chemicals/metabolites using known chemical genetics and human metabolomic data. Metabolites were then prioritized based on the phenotypic similarities between disease- and metabolites. We evaluated mmPredict using 150 metabolites identified using our in-house metabolome profiling study of psoriasis patient samples. mmPredict found 96 of the 150 metabolites and ranked them highly (recall: 0.64, mean ranking: 8.73%, median ranking: 2.33%, p-value: 4.75E-44). These results show that mmPredict is consistent with, as well as a complement to, traditional human metabolomic profiling studies. We then developed a strategy to combine outputs from both systems and found that the oxidative product of linoleic acid, 13(S)-hydroxy-9Z,11E-octadecadienoic acid (13- HODE), ranked highly by both mmPredict and our in-house experiments. Our integrated analysis indicates that 13- HODE may be a mechanistic link between psoriasis and cardiovascular comorbidities associated with psoriasis. In summary, we developed an integrated metabolomic prediction system that combines both human metabolomic studies and mechanism-based prediction and demonstrated its application in the skin disease psoriasis. Our system is highly general and can be applied to other diseases when patient-based metabolomic profiling data becomes more increasingly available. Data is publicly available at: http://nlp.. edu/public/data/mmPredict_PSO.

Topics: Animals; Biomarkers; Disease Models, Animal; Genome; Humans; Linoleic Acids; Metabolome; Metabolomics; Mice; Phenotype; Psoriasis

Oxidative stress plays a key role in the development of type 2 diabetes. However, it is still unknown what kind of oxidative stress underlies the development of type 2 diabetes. We investigated hydroxyoctadecadienoic acid (HODE) isomers, which have been proposed as a biomarker for evaluating oxidative stress in vivo, during the development of diabetes in Tsumura Suzuki Obese Diabetes (TSOD) mouse, a type 2 diabetes model. It was revealed that glucose tolerance and insulin resistance index HOMA-IR in TSOD mice at 5 weeks of age were approximately normal, namely, the mice were in the prediabetic state, but these levels were significantly exacerbated from 8 weeks of age compared with those in Tsumura Suzuki Non Obesity (TSNO) mice (control). Concomitantly, the plasma levels of free-radical-mediated oxidation products, 9- and 13-(E,E)-HODE and 7β-hydroxycholesterol, in TSOD mice were significantly higher than those in TSNO mice at 8, and 8 and 11 weeks of age, respectively. Interestingly, the plasma levels of 10- and 12-(Z,E)-HODE, which are produced specifically by singlet-oxygen-mediated oxidation, in TSOD mice were higher than those in TSNO mice only at 5 weeks of age, and not at 8, 11, and 13 weeks of age. We demonstrated that singlet-oxygen-mediated oxidation occurred in TSOD mice before development of the diabetic phenotypes, including impaired glucose tolerance and insulin resistance. These results suggest that excessive singlet-oxygen-mediated oxidation plays an important role in the pathogenesis of type 2 diabetes.

Topics: Animals; Biomarkers; Diabetes Mellitus, Type 2; Disease Models, Animal; Free Radicals; Glucose Intolerance; Insulin Resistance; Linoleic Acids; Linoleic Acids, Conjugated; Male; Mice; Mice, Inbred Strains; Mice, Obese; Oxidative Stress; Singlet Oxygen

The transient receptor potential vanilloid type 1 (TRPV1) plays a fundamental role in the detection of heat and inflammatory pain responses. Here we investigated the contribution of two potential endogenous ligands [9- and 13- hydroxyoctadecadienoic acid (HODE)] to TRPV1-mediated noxious responses and inflammatory pain responses.. 9- and 13-HODE, and their precursor, linoleic acid, were measured in dorsal root ganglion (DRG) neurons and in the hindpaws of control and carrageenan-inflamed rats by liquid chromatography/tandem electrospray mass spectrometry. Calcium imaging studies of DRG neurons were employed to determine the role of TRPV1 in mediating linoleic acid, 9-HODE- and 13-HODE-evoked responses, and the contribution of 15-lipoxygenase to the generation of the HODEs. Behavioural studies investigated the contribution of 9- and 13-HODE and 15-lipoxygenase to inflammatory pain behaviour.. 9-HODE (35 ± 7 pmol g(-1)) and 13-HODE (32 ± 6 pmol g(-1)) were detected in hindpaw tissue, but were below the limits of detection in DRGs. Following exposure to linoleic acid, 9- and 13-HODE were detected in DRGs and TRPV1 antagonist-sensitive calcium responses evoked, which were blocked by the 15-lipoxygenase inhibitor PD146176 and an anti-13-HODE antibody. Levels of linoleic acid were significantly increased in the carrageenan-inflamed hindpaw (P < 0.05), whereas levels of 9- and 13-HODE were, however, decreased. Intraplantar co-administration of anti-9- and 13-HODE antibodies and treatment with PD146176 significantly (P < 0.01) attenuated carrageenan-induced hyperalgesia.. This study demonstrates that, although 9- and 13-HODE can activate TRPV1 in DRG cell bodies, the evidence for a role of these lipids as endogenous peripheral TRPV1 ligands in a model of inflammatory pain is at best equivocal.

Topics: Animals; Arachidonate 15-Lipoxygenase; Disease Models, Animal; Fluorenes; Ganglia, Spinal; Inflammation; Linoleic Acids; Linoleic Acids, Conjugated; Male; Mice; Pain; Rats, Sprague-Dawley; TRPV Cation Channels

Fatty acid-binding proteins (FABPs) are postulated to serve as lipid shuttles that solubilize hydrophobic fatty acids and deliver them to appropriate intracellular sites. Epidermal FABP (E-FABP/FABP5) is predominantly expressed in keratinocytes and is overexpressed in the actively proliferating tissue characteristic of psoriasis and wound healing. In this study, we found decreased expression of the differentiation-specific proteins keratin 1, involucrin, and loricrin in E-FABP(-/-) keratinocytes relative to E-FABP(+/+) keratinocytes. We also determined that incorporation of linoleic acid was significantly reduced in E-FABP(-/-) keratinocytes. Although linoleic acid did not directly affect keratinocyte differentiation, keratin 1 expression was induced by the linoleic acid derivative 13(S)-hydroxyoctadecadienoic acid (13(S)-HODE), and this induction was concomitant with increased NF-κB activity. In E-FABP(-/-) keratinocytes, the expression of 13(S)-HODE and the subsequent induction of NF-κB activity was lower than in wild-type keratinocytes. The reduction of linoleic acid in E-FABP(-/-) keratinocytes led to decreased cellular 13(S)-HODE content, resulting in decreased keratin 1 expression through downregulation of NF-κB activity. The regulation of fatty acid metabolism by E-FABP during keratinocyte differentiation suggests that E-FABP may have a role in the pathogenesis of psoriasis.

Topics: Animals; Cell Differentiation; Cells, Cultured; Disease Models, Animal; Epidermis; Fatty Acid-Binding Proteins; Fatty Acids; Keratin-1; Keratinocytes; Linoleic Acid; Linoleic Acids; Membrane Proteins; Mice; Mice, Knockout; Neoplasm Proteins; NF-kappa B; Protein Precursors; Psoriasis; Signal Transduction

15-S-Hydroxyeicosatetraenoic acid (15(S)-HETE) and 13-S-hydroxyoctadecadienoic acid (13(S)-HODE), both of which are metabolites of 15-lipoxygenases (15-LOXs), are endogenous ligands for peroxisome proliferator-activated receptor gamma (PPARgamma). The activation of PPARgamma inhibits cell growth and induces apoptosis in some cancers. The role of 15(S)-HETE) and 13(S)-HODE in the development of lung cancer is not clear.. 15-LOXs, 15(S)-HETE and 13(S)-HODE were monitored during the development of mouse lung tumours induced by the tobacco smoke carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and the levels of these markers were determined in 54 human non-small cell lung cancers.. 15-LOXs, 15(S)-HETE and 13(S)-HODE levels were significantly reduced in human lung cancer tissue compared with non-tumour lung tissue (p=0.011 and p=0.022, respectively). In mouse experiments, 15(S)-HETE and 13(S)-HODE started to reduce at 26 and 30 weeks, respectively, after NNK treatment. The time frame of 15(S)-HETE reduction was in line with the decrease in 12/15-LOX mRNA and protein. A significant difference in the number of tumours in NNK-treated mice and controls was not observed until week 34 (p<0.05) and week 38 (p<0.01). The reduction in 12/15-LOX and 15(S)-HETE therefore predated the appearance of lung tumour. Furthermore, PPARgamma activity was decreased in NNK-treated mouse lungs compared with the control, and the decreased PPARgamma activity occurred at the same time points as the reduction in 12/15-LOX and 15(S)-HETE.. These findings indicate that the reduction in 15-LOX, 15(S)-HETE and 13(S)-HODE results in the decreased PPARgamma activity seen in lung tumours and contributes to the development of lung tumours induced by tobacco smoking.

Topics: Animals; Arachidonate 15-Lipoxygenase; Biomarkers, Tumor; Carcinoma, Non-Small-Cell Lung; Cell Transformation, Neoplastic; Disease Models, Animal; Disease Progression; Female; Humans; Hydroxyeicosatetraenoic Acids; Linoleic Acids; Lung; Lung Neoplasms; Mice; Mice, Inbred A; Neoplasm Proteins; Nitrosamines; PPAR gamma

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

To identify novel genes associated with iron metabolism, we performed gene chip studies in two models of iron deficiency: iron-deprived rats and rats deficient in the principal intestinal iron transporter, divalent metal transporter 1 (i.e., Belgrade rats). Affymetrix rat genome gene chips were utilized (RAE230) with cRNA samples derived from duodenum and jejunum of experimental and control animals. Computational analysis and statistical data reduction identified 29 candidate genes, which were induced in both models of iron deficiency. Gene ontology analysis showed enrichment for genes related to lipid homeostasis, and one gene related to this physiological process, a leukocyte type, arachidonate 12-lipoxygenase (Alox15), was selected for further examination. TaqMan real-time PCR studies demonstrated strong induction of Alox15 throughout the small and large intestine, and in the liver of iron-deficient rats. Polyclonal antibodies were developed and utilized to demonstrate that proteins levels are significantly increased in the intestinal epithelium of iron-deprived rats. HPLC analysis revealed altered intestinal lipid metabolism indicative of Alox15 activity, which resulted in the production of biologically active lipid molecules (12-HETE, 13-HODE, and 13-HOTE). The overall effect is a perturbation of intestinal lipid homeostasis, which results in the production of lipids essentially absent in the intestine of control rats. We have thus provided mechanistic insight into the alteration in lipid metabolism that occurs during iron deficiency, in that induction of Alox15 mRNA expression may be the primary event. The resulting lipid mediators may be related to documented alterations in villus structure and cell proliferation rates in iron deficiency, or to structural alterations in membrane lipid composition.

Topics: 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; Algorithms; Animals; Arachidonate 12-Lipoxygenase; Arachidonate 15-Lipoxygenase; Blotting, Western; Cation Transport Proteins; Chromatography, High Pressure Liquid; Cluster Analysis; Disease Models, Animal; Duodenum; Enzyme Induction; Gene Expression Profiling; Immunohistochemistry; Iron Deficiencies; Iron Metabolism Disorders; Jejunum; Linoleic Acids; Lipid Metabolism; Liver; Male; Oligonucleotide Array Sequence Analysis; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction

A non-suppurative chronic arthritis was induced in the juvenile dog knee by intra-articular instillations with Carrageenan. Lipoxygenase products of arachidonic acid were separated from synovial fluid by reversed-phase high-performance liquid chromatography (RP-HPLC). After ten weeks we observed an accumulation of leukotriene B4 (LTB4) in synovial fluid in five out of six experimental knees (0.94 to 5.5 ng/ml), as judged by integrated optical density. Biological activity of LTB4 was confirmed by chemokinesis. LTB4 was not detected in control knees. The 15-lipoxygenase products, 15-hydroxyeicosatetraenoic acid (15-HETE) and 13-hydroxy-9,11-octadecadienoic acid (13-HODD), being inhibitors of 5-lipoxygenase, were found in relatively high levels in the control knees compared to the arthritic knees. The results denote LTB4 as a pro-inflammatory local mediator during carrageenan-induced arthritis; possibly, the decreased levels of 15-HETE and 13-HODD in the arthritic knees may have a regulatory function, thus facilitating LTB4 generation.

Topics: Animals; Arthritis; Carrageenan; Chemotaxis, Leukocyte; Chromatography, High Pressure Liquid; Disease Models, Animal; Dogs; Hydroxyeicosatetraenoic Acids; Leukotriene B4; Linoleic Acids; Lipoxygenase; Synovial Fluid