Methotrexate (MTX) is a widely used immunosuppressive drug. Large-dose of MTX is used for the treatment of cancer while low-dose is used for the treatment of rheumatoid arthritis (RA). This study aimed to explore the effect of MTX on the urinary proteome of rats. MTX was given to rats orally to construct an MTX intragastric administration rat model. The urine of the rats were collected within 10 hours after giving MTX, and the urine proteins of the rats were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). A total of 31 differential proteins were identified, of which 7 proteins were related to the effect MTX and the symptom of RA. The biological processes of some rats reflected the effect of MTX on the body's glutathione metabolism and the JAK/STAT signaling pathway, which indicated that urine proteins have the ability to reflect the effects of MTX on the body of rats. The spectrum of the differential proteins of each single rat showed that different individuals respond to the drug quite differently.
Keywords: methotrexate; proteomics; rheumatoid arthritis; urine.