Comparison of the systemic phospholipid profile in dogs diagnosed with idiopathic inflammatory bowel disease or food-responsive diarrhea before and after treatment

Abstract

Background Inflammatory bowel disease (IBD) and food-responsive diarrhea (FRD) are common chronic enteropathies in dogs, of which the exact pathogenesis has not been fully understood. In people dyslipidemia has been reported in patients with IBD, and potential therapeutic benefits of polyunsaturated fatty acids (PUFA) in the treatment of IBD have been investigated. Studies on the phospholipid profile in dogs with IBD and FRD are still lacking. Aim To investigate the systemic phospholipid profile of dogs with IBD or FRD and to evaluate possible differences in phospholipids before and after treatment. Methods The phospholipids in whole blood and EDTA plasma of 32 dogs diagnosed with either IBD (n = 16) or FRD (n = 16) were analyzed by hydrophilic interaction liquid chromatography (HILIC) prior to and after initiation of treatment, which included an elimination diet enriched with PUFAs. Results A clear separation of the phospholipids between whole blood and plasma was demonstrated on principal component analysis plots. In addition to the type of specimen, treatment and disease severity were the most significant factors determining the variance of the phospholipid profile. An increase in lysolipids was observed after treatment. The phosphatidylcholine (PC) species changed from PC 38:4 before treatment to mainly lysophosphatidylcholine 18:0 after treatment. Furthermore, several differences in the abundance of individual phospholipids were identified between dogs with IBD and dogs with FRD and between treatment statuses using random forest analysis. Conclusion Significant variances were identified in the phospholipid profiles of dogs with IBD and FRD. These were particularly determined by type of specimen used, disease severity and treatment status. After treatment, a shift of phospholipid species towards lysophosphatidylcholine 18:0 was observed. Future studies should further investigate the role of lipids in the pathophysiology of IBD and FRD as well as their potential therapeutic benefits.

Treatment With Hydrolyzed Diet Supplemented With Prebiotics and Glycosaminoglycans Alters Lipid Metabolism in Canine Inflammatory Bowel Disease

“…Another recently published study sought to overcome this weakness utilizing a hydrophilic interaction liquid chromatography of polar lipid classes (28). Interestingly, this study showed significant alterations in lipid metabolites before and after diet and glucocorticoid treatment in IBD dogs (28). However, this study only assessed phospholipids, while our current study examined a large number of phospholipids as well as a large number of other lipids and low molecular weight molecules.…”

“…In our study, we used UHPLC to detect even low levels of lipid metabolites in serum samples from IBD dogs. Another recently published study sought to overcome this weakness utilizing a hydrophilic interaction liquid chromatography of polar lipid classes (28). Interestingly, this study showed significant alterations in lipid metabolites before and after diet and glucocorticoid treatment in IBD dogs (28).…”

“…These methods are considered to be more robust approaches compared to methods based on relative response factors of lipid analytes without internal standards. It is important to note that the study performed by Kalenyak et al ( 28 ) employed a special novel protein diet (i.e., codfish), which is not commercially available in dogs. The results are therefore difficult to apply to a population of dogs treated with commercially available hydrolyzed diets, as was done in our study.…”

“…In veterinary medicine, only a few studies have utilized serum metabolomics analysis in clinical patients (25,26). To our knowledge, only two studies have been reported in dogs with IBD (27,28). These studies have provided some new insights into metabolomic differences in IBD dogs vs. healthy dogs and IBD dogs before and after treatment.…”

The Erythrocyte Membrane Lipidome of Healthy Dogs: Creating a Benchmark of Fatty Acid Distribution and Interval Values

“…Indeed, liberation of SFA, MUFA, and PUFA fatty acids generates potent mediators, such as prostaglandins, leukotrienes, endocannabinoids, and many others that influence dog metabolism in health and diseases (51)(52)(53). There is a growing attention to the lipidomic analysis in animal studies, as reported recently for variations of phospholipids of whole blood and plasma in canine inflammatory bowel disease (53). In this context we believe that the present work on erythrocyte membrane fatty acid cohort in healthy animals could represent the benchmark for assessment of healthy dog molecular profile.…”