To differentiate into metacyclic trypomastigotes by increased cAMP levels that result from the addition of catecholamines, which are tyrosine derivatives that bind to a subclass of Gprotein-coupled receptors. Phospholipids are complex molecules that are essential for intracellular signaling and membrane integrity but are also precursors for several other very important lipid molecules including sphingolipids, ceramides and glycosylphosphatidylinositol anchors. Certain glycosylphosphatidylinositol-anchored proteins play a special role in the virulence of protozoan pathogens as adhesins and/or variable epitopes that are used to evade the immune system, such as the variable surface glycoprotein in T. brucei and T. cruzi. Myo-inositol is an essential nutrient that is used for building phosphatidylinositol and its derivatives in eukaryotes. As a consequence, protozoan pathogens must be able to acquire inositol to proliferate and infect their hosts. Phosphatidylinositol is also the Ginsenoside-F5 precursor for a wide variety of membrane-bound and non-membrane-bound phosphorylated inositol signal transduction molecules. T. cruzi has at least two different myo-inositol transporters based on a biochemical analysis of import activities. The central role of phospholipids in T. cruzi metabolism has been demonstrated by the antiprotozoal activity of several phospholipid analogs. In addition to fatty acids and phospholipids, steroids are another important group of molecules based on their relative metabolite proportion in triatomine feces. The main biological activity associated with this metabolic group is hormonal. For instance, ecdysone, a steroid produced by prothoracic glands, was shown to be involved in the epithelial cell organization of the R. prolixus midgut and the dysregulation of the neuroendocrine system induced by azadirachtin. Interestingly, the epithelial midgut alteration is correlated with parasite death, indicating that the epithelial extracellular membranes are involved in the establishment and development of T. cruzi in the gut of this vector. The beneficial effect of steroids on T. cruzi has been shown in the chronic stage of Chagas disease in humans. In addition, T. cruzi itself is able to produce androgens and estrogens when incubated in the presence of steroid precursors, which suggests the presence of active parasite steroidogenic enzymes and increases the significance of the observation of steroid metabolites in triatomine feces. Glycerolipids are formed through the linkage of fatty acids to glycerol by ester bonds; many of these lipids have biological activities, such as diacylglycerol, platelet-activating factor, choline and ethanolamine, for example. In addition to their role in energy metabolism, glycerolipids have roles in cellular signaling for many biological processes. Of interest in this study, trypanosomatids synthesize lipids from acetyl-CoA and glycerolipids from glycerol through the mevalonate pathway. First, triacylglycerol and glycerophospholipids are synthesized from phosphatidic acid. Basically, phosphatidic acid is dephosphorylated by a Butenafine hydrochloride phosphatidate phosphatase. The resulting diacylglycerol can be directly acetylated by an acyltransferase to form a triacylglycerol or can react with cytidine-diphosphate-choline or CDP-ethanolamine to form phosphatidylcholine or phosphatidylethanolamine, respectively. Ethanolamine phosphate cytidylyltransferase and 
choline phosphate cytidylyltransferase homologs were identified in trypanosomatids. Ethanolamine, phosphatidylcholine and sphingomyelin are classes of phospholipids that are abundant in cell membranes. Another example of a phospholipid with an essential role in the biology of T. cruzi is lysophosphatidylcholine.