Bile acid profiles are altered in obese individuals with asthma. Thus, we sought to better understand how obesity-related systemic changes contribute to lung pathophysiology. We also test the therapeutic potential of nitro-oleic acid (NO2-OA), a regulator of metabolic and inflammatory signaling pathways, to mitigate allergen and obesity-induced lung function decline in a murine model of asthma. Bile acids were measured in the plasma of healthy subjects and individuals with asthma and serum and lung tissue of mice with and without allergic airway disease (AAD). Lung function, indices of inflammation and hepatic bile acid enzyme expression were measured in obese mice with house dust mite-induced AAD treated with vehicle or NO2-OA. Serum levels of glycocholic acid and glycoursodeoxycholic acid clinically correlate with body mass index and airway hyperreactivity whereas murine levels of β-muricholic acid and tauro-β-muricholic acid were significantly increased and positively correlated with impaired lung function in obese mice with AAD. NO2-OA reduced murine bile acid levels by modulating hepatic expression of bile acid synthesis enzymes, with a concomitant reduction in small airway resistance and tissue elastance. Bile acids correlate to body mass index and lung function decline and the signaling actions of nitroalkenes can limit AAD by modulating bile acid metabolism, revealing a potential pharmacologic approach to improving the current standard of care.

• MeSH
• Anti-Asthmatic Agents therapeutic use   MeSH
• Antigens, Dermatophagoides toxicity   MeSH
• Asthma drug therapy   etiology   metabolism   physiopathology   MeSH
• Diet, High-Fat adverse effects   MeSH
• Adult MeSH
• Nitro Compounds therapeutic use   MeSH
• Thinness MeSH
• Liver drug effects   metabolism   MeSH
• Glycocholic Acid blood   MeSH
• Ursodeoxycholic Acid analogs & derivatives   blood   MeSH
• Oleic Acids therapeutic use   MeSH
• Middle Aged MeSH
• Humans MeSH
• Fatty Acids chemistry   physiology   MeSH
• Adolescent MeSH
• Young Adult MeSH
• Mice, Inbred C57BL MeSH
• Mice MeSH
• Obesity complications   metabolism   physiopathology   MeSH
• Lung physiopathology   MeSH
• Drug Evaluation, Preclinical MeSH
• Respiratory Hypersensitivity chemically induced   drug therapy   metabolism   MeSH
• Forced Expiratory Volume MeSH
• Vital Capacity MeSH
• Bile Acids and Salts metabolism   MeSH
• Animals MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Male MeSH
• Mice MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Names of Substances
• Anti-Asthmatic Agents MeSH
• Antigens, Dermatophagoides MeSH
• CXA-10 MeSH Browser
• Nitro Compounds MeSH
• glycoursodeoxycholic acid MeSH Browser
• Glycocholic Acid MeSH
• Ursodeoxycholic Acid MeSH
• Oleic Acids MeSH
• Fatty Acids MeSH
• Bile Acids and Salts MeSH

Many diseases accompanied by chronic inflammation are connected with dysregulated activation of macrophage subpopulations. Recently, we reported that nitro-fatty acids (NO2-FAs), products of metabolic and inflammatory reactions of nitric oxide and nitrite, modulate macrophage and other immune cell functions. Bone marrow cell suspensions were isolated from mice and supplemented with macrophage colony-stimulating factor (M-CSF) or granulocyte-macrophage colony-stimulating factor (GM-CSF) in combination with NO2-OA for different times. RAW 264.7 macrophages were used for short-term (1-5min) experiments. We discovered that NO2-OA reduces cell numbers, cell colony formation, and proliferation of macrophages differentiated with colony-stimulating factors (CSFs), all in the absence of toxicity. In a case of GM-CSF-induced bone marrow-derived macrophages (BMMs), NO2-OA acts via downregulation of signal transducer and activator of transcription 5 and extracellular signal-regulated kinase (ERK) activation. In the case of M-CSF-induced BMMs, NO2-OA decreases activation of M-CSFR and activation of related PI3K and ERK. Additionally, NO2-OA also attenuates activation of BMMs. In aggregate, we demonstrate that NO2-OA regulates the process of macrophage differentiation and that NO2-FAs represent a promising therapeutic tool in the treatment of inflammatory pathologies linked with increased accumulation of macrophages in inflamed tissues.

• Keywords
• Differentiation, Growth factors, Inflammation, Macrophages, Nitro-fatty acids, Nitro-oleic acid, Signaling pathways,
• MeSH
• Cell Differentiation drug effects   MeSH
• Bone Marrow Cells drug effects   MeSH
• Extracellular Signal-Regulated MAP Kinases genetics   MeSH
• Colony-Stimulating Factors genetics   MeSH
• Phosphatidylinositol 3-Kinases genetics   MeSH
• Oleic Acid administration & dosage   chemistry   MeSH
• Macrophages drug effects   MeSH
• MAP Kinase Signaling System drug effects   MeSH
• Mice MeSH
• Nitric Oxide administration & dosage   chemistry   MeSH
• RAW 264.7 Cells MeSH
• Gene Expression Regulation, Neoplastic drug effects   MeSH
• STAT5 Transcription Factor genetics   MeSH
• Inflammation drug therapy   genetics   pathology   MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Names of Substances
• Extracellular Signal-Regulated MAP Kinases MeSH
• Colony-Stimulating Factors MeSH
• Phosphatidylinositol 3-Kinases MeSH
• Oleic Acid MeSH
• Nitric Oxide MeSH
• STAT5 Transcription Factor MeSH

RATIONALE: Pulmonary hypertension (PH) represents a serious health complication accompanied with hypoxic conditions, elevated levels of asymmetric dimethylarginine (ADMA), and overall dysfunction of pulmonary vascular endothelium. Since the prevention strategies for treatment of PH remain largely unknown, our study aimed to explore the effect of nitro-oleic acid (OA-NO2), an exemplary nitro-fatty acid (NO2-FA), in human pulmonary artery endothelial cells (HPAEC) under the influence of hypoxia or ADMA. METHODS: HPAEC were treated with OA-NO2 in the absence or presence of hypoxia and ADMA. The production of nitric oxide (NO) and interleukin-6 (IL-6) was monitored using the Griess method and ELISA, respectively. The expression or activation of different proteins (signal transducer and activator of transcription 3, STAT3; hypoxia inducible factor 1α, HIF-1α; endothelial nitric oxide synthase, eNOS; intercellular adhesion molecule-1, ICAM-1) was assessed by the Western blot technique. RESULTS: We discovered that OA-NO2 prevents development of endothelial dysfunction induced by either hypoxia or ADMA. OA-NO2 preserves normal cellular functions in HPAEC by increasing NO production and eNOS expression. Additionally, OA-NO2 inhibits IL-6 production as well as ICAM-1 expression, elevated by hypoxia and ADMA. Importantly, the effect of OA-NO2 is accompanied by prevention of STAT3 activation and HIF-1α stabilization. CONCLUSION: In summary, OA-NO2 eliminates the manifestation of hypoxia- and ADMA-mediated endothelial dysfunction in HPAEC via the STAT3/HIF-1α cascade. Importantly, our study is bringing a new perspective on molecular mechanisms of NO2-FAs action in pulmonary endothelial dysfunction, which represents a causal link in progression of PH. Graphical Abstract ᅟ.

• Keywords
• Asymmetric dimethylarginine, Human pulmonary artery endothelial cell, Hypoxia, Nitro-oleic acid, Pulmonary hypertension,
• MeSH
• Arginine analogs & derivatives   pharmacology   MeSH
• Pulmonary Artery cytology   MeSH
• Cell Adhesion drug effects   MeSH
• Endothelial Cells drug effects   metabolism   physiology   MeSH
• Hypoxia-Inducible Factor 1, alpha Subunit metabolism   MeSH
• Cell Hypoxia drug effects   MeSH
• Interleukin-6 metabolism   MeSH
• Cells, Cultured MeSH
• Oleic Acids pharmacology   MeSH
• Humans MeSH
• Intercellular Adhesion Molecule-1 metabolism   MeSH
• Nitric Oxide metabolism   MeSH
• Cell Movement drug effects   MeSH
• Nitric Oxide Synthase Type III metabolism   MeSH
• STAT3 Transcription Factor antagonists & inhibitors   metabolism   MeSH
• Cell Survival drug effects   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Arginine MeSH
• Hypoxia-Inducible Factor 1, alpha Subunit MeSH
• HIF1A protein, human MeSH Browser
• IL6 protein, human MeSH Browser
• Interleukin-6 MeSH
• Oleic Acids MeSH
• Intercellular Adhesion Molecule-1 MeSH
• N,N-dimethylarginine MeSH Browser
• NOS3 protein, human MeSH Browser
• Nitric Oxide MeSH
• STAT3 protein, human MeSH Browser
• Nitric Oxide Synthase Type III MeSH
• STAT3 Transcription Factor MeSH

BACKGROUND: Inflammatory-mediated pathological processes in the endothelium arise as a consequence of the dysregulation of vascular homeostasis. Of particular importance are mediators produced by stimulated monocytes/macrophages inducing activation of endothelial cells (ECs). This is manifested by excessive soluble pro-inflammatory mediator production and cell surface adhesion molecule expression. Nitro-fatty acids are endogenous products of metabolic and inflammatory reactions that display immuno-regulatory potential and may represent a novel therapeutic strategy to treat inflammatory diseases. The purpose of our study was to characterize the effects of nitro-oleic acid (OA-NO2) on inflammatory responses and the endothelial-mesenchymal transition (EndMT) in ECs that is a consequence of the altered healing phase of the immune response. METHODS: The effect of OA-NO2 on inflammatory responses and EndMT was determined in murine macrophages and murine and human ECs using Western blotting, ELISA, immunostaining, and functional assays. RESULTS: OA-NO2 limited the activation of macrophages and ECs by reducing pro-inflammatory cytokine production and adhesion molecule expression through its modulation of STAT, MAPK and NF-κB-regulated signaling. OA-NO2 also decreased transforming growth factor-β-stimulated EndMT and pro-fibrotic phenotype of ECs. These effects are related to the downregulation of Smad2/3. CONCLUSIONS: The study shows the pleiotropic effect of OA-NO2 on regulating EC-macrophage interactions during the immune response and suggests a role for OA-NO2 in the regulation of vascular endothelial immune and fibrotic responses arising during chronic inflammation. GENERAL SIGNIFICANCE: These findings propose the OA-NO2 may be useful as a novel therapeutic agent for treatment of cardiovascular disorders associated with dysregulation of the endothelial immune response.

• Keywords
• Endothelial cells, Endothelial-mesenchymal transition, Macrophages, Nitro-fatty acids, Nitro-oleic acid, Vascular inflammation,
• MeSH
• Endothelium, Vascular cytology   drug effects   metabolism   MeSH
• Endothelial Cells drug effects   metabolism   MeSH
• Epithelial-Mesenchymal Transition * MeSH
• Oleic Acids pharmacology   MeSH
• Humans MeSH
• Macrophages drug effects   metabolism   MeSH
• MAP Kinase Signaling System MeSH
• Mice MeSH
• NF-kappa B metabolism   MeSH
• Smad Proteins metabolism   MeSH
• Transforming Growth Factor beta pharmacology   MeSH
• STAT Transcription Factors metabolism   MeSH
• Inflammation metabolism   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Names of Substances
• 10-nitro-oleic acid MeSH Browser
• Oleic Acids MeSH
• NF-kappa B MeSH
• Smad Proteins MeSH
• Transforming Growth Factor beta MeSH
• STAT Transcription Factors MeSH