Lung Lipidomic Alterations in Beagle Dogs Infected with Toxocara canis

SIMPLE SUMMARY: Toxocariasis is mainly caused by Toxocara canis, and to a lesser extent, Toxocara cati, and is a globally distributed zoonotic parasitic disease. Lipidomics is a discipline that has been developed after genomics and proteomics, and it is an important means of studying systems biology. In this study, we used liquid chromatography–tandem mass spectrometry (LC-MS/MS) to comprehensively examine the lipidomic alterations in the lungs of Beagle dogs infected with T. canis, and to analyze the differential lipids to reveal their potential biological functions. There were 63, 88, and 157 lipid species that changed significantly at 24 hpi, 96 hpi, and 36 dpi, respectively. Further analysis of the functions of these differential lipids, such as triglyceride (TG), lysophosphatidylserine (LPS), and ceramides (Cer), will better reveal the mechanism of T. canis pathogenesis. ABSTRACT: Toxocariasis, mainly caused by Toxocara canis, and to a lesser extent, Toxocara cati, is a neglected parasitic zoonosis. The mechanisms that underlie the changes in lipid metabolism of T. canis infection in Beagle dogs’ lungs remain unclear. Lipidomics is a rapidly emerging approach that enables the global profiling of lipid composition by mass spectrometry. In this study, we performed a non-targeted lipidomic analysis of the lungs of Beagle dogs infected with the roundworm T. canis using liquid chromatography–tandem mass spectrometry (LC-MS/MS). A total of 1197 lipid species were identified, of which 63, 88, and 157 lipid species were significantly altered at 24 h post-infection (hpi), 96 hpi, and 36 days post-infection (dpi), respectively. This global lipidomic profiling identified infection-specific lipid signatures for lung toxocariasis, and represented a comprehensive comparison between the lipid composition of dogs’ lungs in the presence and absence of T. canis infection. The potential roles of the identified lipid species in the pathogenesis of T. canis are discussed, which has important implications for better understanding the interaction mechanism between T. canis and the host lung.