Serum amino acid profile in 51 dogs with immunosuppressant-responsive enteropathy (IRE): a pilot study on clinical aspects and outcomes

Abstract

Background: Lower levels of tryptophan (TRP) have been identified in people with inflammatory bowel disease and in dogs with protein-losing enteropathy (PLE). No data on serum amino acids (AAs) but some on plasma in canine immunosuppressant-responsive enteropathy (IRE) are available. The aim of this study is to compare serum AAs between healthy and IRE dogs, considering clinicopathological variables and follow-up. Results: Twenty-six healthy control dogs (CD) and 51 IRE dogs were included. IRE was diagnosed after the exclusion of extra-intestinal diseases and food and antibiotic responsive enteropathies. The canine chronic enteropathy clinical activity index (CCECAI) was assessed at presentation and during the clinical follow-up. In CD and IRE dogs, 19 different serum AAs were measured. IRE dogs were classified into responders, partial responders and non-responders, based on CCECAI after 1 month, and divided into PLE and non-PLE, based on albumin level. IRE dogs showed lower L-Tyrosine (TYR), L-Phenylalanine (PHE) and TRP (p < 0.001) and higher L-Serine (SER), L-Glutamic acid (GLU), L-Arginine (p < 0.001), L-Threonine (p = 0.013), Proline (p = 0.044), L-Cysteine (p = 0.003), L-Valine (p = 0.018), L-Lysine (p = 0.01) and L-Isoleucine (p = 0.005) than CDs. PLE dogs showed lower L-Histidine (HIS) (p = 0.008), PHE (p = 0.005) and TRP (p = 0.005) than non-PLE dogs. In IRE dogs, median GLU was significantly lower in dogs with BCS 3/9 than BCS 5/9 category (p = 0.036). Total protein was positively correlated with PHE and TRP (both p = 0.031, r = 0.30) and albumin was positively correlated with HIS (p = 0.025, r = 0.31), PHE and TRP (both p = 0.001, r = 0.46). HIS (p = 0.041), PHE (p = 0.047) and TRP (p = 0.044) concentrations were significantly lower in nonresponders than in responders and partial responders. Conclusions:This study may suggest further investigation on serum, HIS, PHE, TRP and TYR as markers of intestinal disease and proposed HIS, PHE and TRP as prognostic marker for response to therapy.

Plasma amino acid profiles in dogs with closed extrahepatic portosystemic shunts are only partially improved 3 months after successful gradual attenuation

“…27 In a recent study in which amino acid profiles of dogs with congenital PSS, dogs with chronic hepatitis, and healthy dogs were analyzed, serum concentrations of BCAAs were significantly lower whereas serum concentrations of tyrosine and phenylalanine (both AAAs) were significantly higher, leading to a lower BCAA-to-AAA ratio in dogs with congenital PSS compared to healthy dogs and dogs with chronic hepatitis. 13 Although both tyrosine and phenylalanine concentrations were very high at diagnosis in our study, all BCAAs were at the lower end of the reference range reported in dogs, 18,19,[28][29][30] which is consistent with previous studies. [11][12][13] Although valine significantly increased after surgical attenuation, it remained within normal limits.…”

“…An age‐ and size‐matched healthy control group could have been included to strengthen our findings. Blood amino acid concentrations in healthy dogs however vary among studies, with all studies describing relatively wide ranges 18,19,30 . In addition, differences in reported normal values can be explained by the fact that most studies only included a small number of apparently healthy dogs that received different types of food, and also by the fact that amino acids were analyzed using different laboratory techniques.…”

The Impact of Chronic Inflammatory Enteropathy on Dogs’ Quality of Life and Dog-Owner Relationship

“…The response to therapies was evaluated by calculating ΔCCECAI% (difference between the CCECAI on the first visit and that at the follow-up, divided by the value of the CCECAI on the first visit and then multiplied by 100) and defining it complete response when ΔCCECAI > 75%, partial response when ΔCCECAI was between 25 and 75%, and no response when ΔCCECAI < 25% [ 24 ]. Partial and complete responders were assigned to the responders group.…”

A Preliminary Metabolomic Study of Yorkshire Terrier Enteropathy

“…Several studies on canine enteropathy have reported changes in metabolite profiles, especially in the short-chain fatty acid and amino acid metabolism; however, data are scarce and inconsistent [ 8 , 9 , 10 , 11 , 12 , 13 ]. Confounding factors like previous treatment, breed, age, sex, and different biological samples and methodological approaches may have caused discrepancies between previous studies [ 14 ].…”