Plasma untargeted lipidomics based on UHPLC-Orbitrap-MS reveals potential biomarkers and the pathogenesis involved in Mycoplasma bovis pneumonia.

Abstract

Mycoplasma bovis is considered a major pathogen involved in the bovine respiratory disease complex (BRDC). This pathogen is primarily associated with pneumonia in calves and feedlot cattle, causing significant economic losses to the global cattle industry. The challenges in early diagnosis and limited understanding of host-pathogen interactions highlight the need for novel biomarkers and pathogenic insights. This study employed ultra-high-performance liquid chromatography-Orbitrap mass spectrometry (UHPLC-Orbitrap-MS)-based untargeted lipidomics to comprehensively profile plasma lipid alterations in calves experimentally infected with M. bovis strain NX114. Histopathological examination confirmed characteristic pulmonary lesions, including inflammatory cell infiltration, alveolar epithelial necrosis, and interstitial fibrosis. Lipidomic analysis identified 313 significantly dysregulated lipid molecules across 49 subclasses. Glycerophospholipid metabolism emerged as the most prominently disturbed pathway. Notably, phosphatidylcholine PC 32:0 was validated as a potential diagnostic biomarker, demonstrating high discriminatory power (AUC = 0.97). These findings elucidate the profound lipid metabolic disturbances induced by M. bovis infection, provide new mechanistic insights into its pathogenesis related to membrane stability and immune regulation, and underscore the potential of plasma lipidomics for developing early diagnostic strategies by identifying quantifiable lipid biomarkers associated with early host metabolic remodeling, and for revealing dysregulated lipid metabolic pathways that may serve as host-targeted therapeutic intervention points in bovine mycoplasmosis.