Prolonged dexamethasone (Dex) administration leads to serious adverse and decrease brain and heart size, muscular atrophy, hemorrhagic liver, and presence of kidney cysts. Herein, we used an untargeted proteomic approach using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for simultaneous identification of changes in proteomes of the major organs in Sprague-Dawley (SD rats post Dex treatment. The comparative and quantitative proteomic analysis of the brain, heart, muscle, liver, and kidney tissues revealed differential expression of proteins (n = 190, 193, 39, 230, and 53, respectively) between Dex-treated and control rats. Functional network analysis using ingenuity pathway analysis (IPA revealed significant differences in regulation of metabolic pathways within the morphologically changed organs that related to: (i) brain-cell morphology, nervous system development, and function and neurological disease; (ii) heart-cellular development, cellular function and maintenance, connective tissue development and function; (iii) skeletal muscle-nucleic acid metabolism, and small molecule biochemical pathways; (iv) liver-lipid metabolism, small molecular biochemistry, and nucleic acid metabolism; and (v) kidney-drug metabolism, organism injury and abnormalities, and renal damage. Our study provides a comprehensive description of the organ-specific proteomic profilesand differentially altered biochemical pathways, after prolonged Dex treatement to understand the molecular basis for development of side effects.
Keywords: LC-MS/M; dexamethasone; glucocorticoid side effects; label-free proteomics; network pathway; proteomic expression; rat tissues.