Comprehensive profiling of lipid metabolites in urine of canine patients with liver mass

Abstract

Fatty acids are an essential component of mammalian bodies. They go through different metabolic pathways depending on physiological states and inflammatory stimuli. In this study, we conducted a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based comprehensive analysis of lipid metabolites in urine of canine patients with liver mass. There were significant differences in quantity of some lipid metabolites that may be closely associated with the disease and/or general inflammatory responses, including increased metabolites of prostaglandin E₂ and/or PGF_2α. We demonstrated that our approach of profiling lipid metabolites in the urine is useful in gaining insights into the disease. These findings may also have an application as a screening test or a diagnosis tool for canine liver mass.

Keywords: dog; lipid metabolite; liver mass; urine.

Fig. 1.

Comparison of lipid metabolites derived from arachidonic acid between healthy group and liver mass group. Quantity of lipid metabolites with significant difference (*) between healthy group (n=12) and liver mass group (n=7). Values are represented as ratio of peak area of each metabolite to that of corresponding internal standard, normalized by the creatinine concentration of the sample. Lipid metabolites relevant to pathways above with noticeable changes that did not reach statistical significance are also shown. PG: prostaglandin.

Fig. 2.

Comparison of lipid metabolites in other classes between healthy group and liver mass group. Quantity of lipid metabolites with significant difference (*) between healthy group (n=12) and liver mass group (n=7). Values are represented as ratio of peak area of each metabolite to that of corresponding internal standard, normalized by the creatinine concentration of the sample. DHA: docosahexaenoic acid, EPA: eicosapentaenoic acid, PAF: platelet activating factor, PG: prostaglandin.