Logo Medical Science Monitor

Call: +1.631.470.9640
Mon - Fri 10:00 am - 02:00 pm EST

Contact Us

Logo Medical Science Monitor Logo Medical Science Monitor Logo Medical Science Monitor

01 August 2005

Expression regulation of MAO isoforms in monocytic cells in response to Th2cytokines.

Pavlos Chaitidis, Ellen Billett, Ralf J Kuban, Ute Ungethuem, Hartmut Kuhn

Med Sci Monit 2005; 11(8): BR259-265 :: ID: 199709

Abstract

Background: Th2-cytokines, such as interleukins-4 and -13 (IL-4, IL-13),have been identified as alternative stimuli of monocytes/macrophages. We have recently profiled the gene-expressionpattern of IL-4-teated human peripheral monocytes and found that 15-lipoxygenase-1 (15-LOX1) and monoamineoxidase A (MAO-A) are among the five most strongly upregulated gene products in IL-4-treated cells. Transfectionof monocytic cells (U937) with 15-LOX1 also induced MAO-A expression. These data suggested that 15-LOX1products might play a role in the IL4-induced signaling cascade leading to expression of MAO-A in humanmonocytes. Material/Methods: To test this hypothesis we incubated wild-type and 15-LOX1-transfected U937cells with different concentrations of either IL-4 or 15-LOX-products [13S-H(p)ODE, 15S-H(p)ETE] andquantified the expression of 15-LOX1, MAO-A, and MAO-B by activity assays and real-time RT-PCR. Results:Wild-type U937 cells express neither MAO-A nor MAO-B, but after three days of IL4 treatment, MAO-A mRNAwas detected. A similar isoform-specific expression of MAO-A mRNA was observed when U937 cells were transfectedwith 15-LOX1 or when the cells were incubated with primary 15-LOX1 products (hydroperoxy fatty acids)or H2O2. In contrast, the corresponding hydroxy fatty acids were ineffective. Conclusions: These dataindicate that increased intracellular peroxide concentrations (oxidative stress) induce MAO-A expressionin monocytes/macrophages, which normally do not express the enzyme. Our findings also suggest that IL-4-inducedupregulation of MAO-A expression in human peripheral monocytes may proceed via 15-LOX1-dependent and15-LOX1-independent pathways. The biological role of MAO-A expression for monocyte function is discussed.

Keywords: Gene Expression Regulation, Enzymologic - genetics, Arachidonate 15-Lipoxygenase - metabolism, Gene Expression Regulation, Enzymologic - genetics, Interleukin-4 - pharmacology, Isoenzymes - metabolism, Linoleic Acid - metabolism, Monoamine Oxidase - metabolism, Monocytes - enzymology, Th2 Cells - metabolism

Add Comment 0 Comments

608 5

Editorial

01 December 2023 : Editorial  

Editorial: Outbreaks of Post-Pandemic Childhood Pneumonia and the Re-Emergence of Endemic Respiratory Infections

Dinah V. Parums

DOI: 10.12659/MSM.943312

Med Sci Monit 2023; 29:e943312

0:00

In Press

04 Dec 2023 : Animal Research  

Effects of Intrathecal Ketamine on Cerebrospinal Fluid Levels of Brain-Derived Neurotrophic Factor and Mech...

Med Sci Monit In Press; DOI:  

01 Dec 2023 : Clinical Research  

Risk Factors and Clinical Outcomes of COVID-19 Infection in Multiple Sclerosis Patients: A Retrospective St...

Med Sci Monit In Press; DOI:  

30 Nov 2023 : Review article  

Decoding the Neurological Sequelae of General Anesthesia: A Review

Med Sci Monit In Press; DOI:  

30 Nov 2023 : Clinical Research  

Enhanced Pain Relief and Muscle Growth in Individuals with Low Back Instability: The Impact of Blood Flow R...

Med Sci Monit In Press; DOI:  

Most Viewed Current Articles

13 Nov 2021 : Clinical Research  

Acceptance of COVID-19 Vaccination and Its Associated Factors Among Cancer Patients Attending the Oncology ...

DOI :10.12659/MSM.932788

Med Sci Monit 2021; 27:e932788

0:00

30 Dec 2021 : Clinical Research  

Retrospective Study of Outcomes and Hospitalization Rates of Patients in Italy with a Confirmed Diagnosis o...

DOI :10.12659/MSM.935379

Med Sci Monit 2021; 27:e935379

0:00

14 Dec 2022 : Clinical Research  

Prevalence and Variability of Allergen-Specific Immunoglobulin E in Patients with Elevated Tryptase Levels

DOI :10.12659/MSM.937990

Med Sci Monit 2022; 28:e937990

0:00

08 Mar 2022 : Review article  

A Review of the Potential Roles of Antioxidant and Anti-Inflammatory Pharmacological Approaches for the Man...

DOI :10.12659/MSM.936292

Med Sci Monit 2022; 28:e936292

0:00

Your Privacy

We use cookies to ensure the functionality of our website, to personalize content and advertising, to provide social media features, and to analyze our traffic. If you allow us to do so, we also inform our social media, advertising and analysis partners about your use of our website, You can decise for yourself which categories you you want to deny or allow. Please note that based on your settings not all functionalities of the site are available. View our privacy policy.

Medical Science Monitor eISSN: 1643-3750
Medical Science Monitor eISSN: 1643-3750