Originally fats were generally considered mere sources of energy and components of biological membranes. Aside from the eicosanoids few lipid-derived bioactive compounds had been characterized. However, research over the past 15-20 years has demonstrated a widely diverse array of biological activities associated with fatty acids and fatty acid derivatives as well as other lipid compounds. Bioactive lipids span the gamut of structural entities from simple saturated fatty acids to complex molecules such as those derived from various omega-3 and omega-6 polyunsaturated fatty acids (PUFA) and those derived from sphingosine. Many bioactive lipids result from the activities of the various phospholipases (see below and in the Signal Transduction page) and phospholipid kinases that are themselves activated by a variety of signal-transducing receptors. Bioactive lipids in the human body mainly refer to eicosanoids. It is a large class of biologically active unsaturated fatty acids produced by the oxidation of twenty-carbon polyunsaturated fatty acids. It is an important inflammatory factor widely present in body fluids and tissues, regulating many physiological and pathological processes in the body. They are a large class of hormone analogues produced by many mammalian tissues, and they only work in the organs that are produced, so they are called autocrine regulatory molecules. G-protein coupled receptor is bioactive lipids which play an important role in energy homeostasis, cell proliferation, metabolism, inflammatory homeostasis, and process regulation; thus, their effects will be exerted through their binding with specific receptors. Specifically, these come from the GPCRs. A series of human genome sequences have been identified, which are characterized by being activated by free fatty acids and lipid molecules The eicosanoids present a very important class of bioactive lipid mediators. Their high structure activity relationship in combination with typically several stereo-centers and double bonds as well as their generally high bioactivity, does not only warrant highly sensitive but also selective analysis techniques. Today’s predominantly used techniques are ultra-high pressure liquid chromatography and gas chromatography combined with (tandem) mass spectrometry. GPR44 was originally identified as an orphan GPCR but was subsequently shown to bind and be activated by prostaglandin D2 (PGD2). The gene encoding the originally identified GPR44 protein is now termed PTGDR2 and represents one of two genes encoding receptors for prostaglandin D family lipids. The other gene in this family of prostaglandin D receptors is PTGDR1. The protein encoded by the PTGDR1 gene is commonly identified as DP1 and the protein encoded by the PTGDR2 gene is commonly identified as DP2. Additionally, leukotrienes contribute to the pathophysiology of asthma, especially in patients with aspirin-exacerbated respiratory disease; lysophosphatidic acid can stimulate cell proliferation, and aberrant LPA-signaling has been linked to cancer in numerous ways. Studies of bioactive lipids have helped us to understand more about the formation of thrombosis in cardiovascular disease. And this can help to treat cardiovascular diseases by promoting or inhibiting these active lipids. Through the release of proinflammatory and cytotoxic oxidants, cytokines, proteases, and bioactive lipids, these cells can contribute to tissue damage. More recent studies suggest that, at later times following injury, macrophages and mediators they generate also play a key role in downregulating the inflammatory response and initiating tissue repair. Journal URLs https://www.walshmedicalmedia.com/clinical-medical-biochemistry.html Submission url: https://www.walshmedicalmedia.com/clinical-medical-biochemistry/submit-manuscript.html Instructions for author: https://www.walshmedicalmedia.com/clinical-medical-biochemistry/instructionsforauthors.html https://www.walshmedicalmedia.com/clinical-medical-biochemistry/archive.html https://www.walshmedicalmedia.com/clinical-medical-biochemistry/inpress.html