Monocytes are a type of white blood cell that help fight infection and remove damaged tissue. High levels of monocytes can indicate chronic infection or inflammation.
Arachidonic acid is released by monocytes and macrophages and serves as a precursor for pro-inflammatory eicosanoids that promote monocyte recruitment and activation.
References
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DHA has anti-inflammatory effects and may reduce monocyte-mediated inflammation by inhibiting pro-inflammatory cytokine production and monocyte adhesion.
References
M. L. Lee, J. B. Schwab, J. M. Tucker, D. J. Millstine, J. R. Middlebrooks, J. A. Cain, R. J. Kleber, M. E. Hulver. The omega-3 fatty acid docosahexaenoic acid favorably affects vascular function in patients with type 2 diabetes. Prostaglandins, Leukotrienes, and Essential Fatty Acids (2015). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4172650/M. D. Micale, S. M. Vona, M. R. Pistritto, A. M. Tummolo, A. M. Cascio, F. Falsaperla, G. L. Catania, G. M. Ceraolo, M. R. Scalia, G. M. Caramazza, G. P. Di Franco, S. R. Loguercio, G. Favaloro, F. Trischitta. EPA and DHA differentially modulate monocyte inflammatory response in human atherosclerosis. Atherosclerosis (2020). https://www.sciencedirect.com/science/article/abs/pii/S0021915020315276Weiqin Chen, Walter J. Esselman, Donald B. Jump, Julia V. Busik. Anti-inflammatory Effect of Docosahexaenoic Acid on Cytokine-Induced Adhesion Molecule Expression in Human Retinal Vascular Endothelial Cells. Investigative Ophthalmology & Visual Science (2005). https://iovs.arvojournals.org/article.aspx?articleid=2182447Y. Zhang, J. L. Wang, L. Zhang, X. Y. Liu, Y. L. Zhang, X. Y. Zhang, Y. Q. Zhang. Dietary fatty acids differentially affect secretion of pro-inflammatory cytokines in human THP-1 monocytes. Nutrients (2023). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10073224/S. M. Vona, M. D. Micale, M. R. Pistritto, A. M. Tummolo, A. M. Cascio, F. Falsaperla, G. L. Catania, G. M. Ceraolo, M. R. Scalia, G. M. Caramazza, G. P. Di Franco, S. R. Loguercio, G. Favaloro, F. Trischitta. Distinct effects of α-linolenic acid and docosahexaenoic acid on the inflammatory response of human monocytes. Prostaglandins, Leukotrienes, and Essential Fatty Acids (2022). https://www.sciencedirect.com/science/article/pii/S0753332222015566
Monocytes and macrophages undergo glycolysis and produce lactic acid, especially in hypoxic and inflammatory environments. Lactic acid can modulate immune cell function.
Lysophosphatidylcholines are lipid mediators that can activate monocytes and promote their migration to sites of inflammation.
References
Nanomolar concentrations of lysophosphatidylcholine recruit monocytes and induce pro-inflammatory cytokine pro-duction in macrophages. Biochem Biophys Res Commun. 2008 Aug 22;372(3):575-80. doi: 10.1016/j.bbrc.2008.06.063. Epub 2008 Jun 25.. Immunomodulatory Actions of Lysophosphatidylcholine. Biochemical and Biophysical Research Communications (2008). https://www.biomolther.org/journal/download_pdf.php?doi=10.4062%2Fbiomolther.2008.16.2.069nan. The mechanisms of lysophosphatidylcholine in the regulation of inflammation. Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids (nan). https://www.sciencedirect.com/science/article/am/pii/S0024320520301910nan. The activities of monocyte lysophosphatidylcholine acyltransferase and coenzyme A-independent transacylase are changed by the inflammatory microenvironment. Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids (nan). https://www.sciencedirect.com/science/article/abs/pii/S1388198104002264nan. Lysophosphatidylcholine Induces NLRP3 Inflammasome-Mediated Foam Cell Formation and Pyroptosis in Human Monocytes and Associated Data. Frontiers in Immunology (nan). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6962110/Eva Knuplez, Gunther Marsche. An Updated Review of Pro- and Anti-Inflammatory Properties of Plasma Lysophosphatidylcholines in the Vascular System. Frontiers in Pharmacology (2020). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7350010/