Fecal Concentrations of Long-Chain Fatty Acids, Sterols, and Unconjugated Bile Acids in Cats with Chronic Enteropathy

Abstract

Chronic enteropathy (CE) in cats encompasses food-responsive enteropathy, chronic inflammatory enteropathy (or inflammatory bowel disease), and low-grade intestinal T-cell lymphoma. While alterations in the gut metabolome have been extensively studied in humans and dogs with gastrointestinal disorders, little is known about the specific metabolic profile of cats with CE. As lipids take part in energy storage, inflammation, and cellular structure, investigating the lipid profile in cats with CE is crucial. This study aimed to measure fecal concentrations of various fatty acids, sterols, and bile acids. Fecal samples from 56 cats with CE and 77 healthy control cats were analyzed using gas chromatography-mass spectrometry, targeting 12 fatty acids, 10 sterols, and 5 unconjugated bile acids. Fecal concentrations of nine targeted fatty acids and animal-derived sterols were significantly increased in cats with CE. However, fecal concentrations of plant-derived sterols were significantly decreased in cats with CE. Additionally, an increased percentage of primary bile acids was observed in a subset of cats with CE. These findings suggest the presence of lipid maldigestion, malabsorption, and inflammation in the gastrointestinal tract of cats with CE. Understanding the lipid alterations in cats with CE can provide insights into the disease mechanisms and potential future therapeutic strategies.

Temporal Variability of the Dominant Fecal Microbiota in Healthy Adult Cats

“…A significant correlation has been observed between the fecal abundance of C. hiranonis and the percentage of fecal primary BAs in this and other studies [ 49 , 50 , 51 ], suggesting C. hiranonis as the main BA convertor in cats. Notably, even in cats with relatively low abundance (below the lower limit of the RI, but above 3 log DNA), the conversion of BAs was present in all healthy cats [ 31 ]. Whether C. hiranonis is the only species that converts BA in cats requires further investigations.…”

“…To examine the association between C. hiranonis and BA metabolism, concentrations of unconjugated BAs (cholic acid, chenodeoxycholic acid, deoxycholic acid, lithocholic acid, and ursodeoxycholic acid) in the fecal samples were quantified using a validated gas chromatography coupled with mass spectrometry (GC-MS) method [ 31 ]. Leftover fecal samples from a total of 78 fecal samples from healthy cats and 22 samples from cats receiving antibiotics were included in the analysis.…”

“…In dogs, Clostridium hiranonis (also known as Peptacetobacter hiranonis ) has been extensively studied and identified as the major convertor of primary BAs into secondary BAs [ 29 ]. A reduction in C. hiranonis in feces has been reported in dogs [ 30 ] and cats with chronic enteropathy (CE) [ 31 ]. Previous studies also showed that fecal primary BAs increased in cats with CE [ 31 ] and kittens receiving antibiotics [ 32 ].…”

“…A reduction in C. hiranonis in feces has been reported in dogs [ 30 ] and cats with chronic enteropathy (CE) [ 31 ]. Previous studies also showed that fecal primary BAs increased in cats with CE [ 31 ] and kittens receiving antibiotics [ 32 ]. The balance and composition of BAs have been linked to the composition of the microbiota in humans [ 33 , 34 ], rats [ 35 ], and dogs [ 36 , 37 ].…”

Gut microbiota in cats with inflammatory bowel disease and low-grade intestinal T-cell lymphoma

“…However, it provides partial assessment of the gut microbiota composition and does not bring better insights into the interactions between gut microbiota and feline CE. Metabolic alterations resembling those described in human IBD and relating to tryptophan, arachidonic acid, glutathione and lipids have also been underlined in pet cats with CE ( Marsilio et al, 2021 ; Barko et al, 2023 ; Miller et al, 2023 ; Sung et al, 2023 ). Additional studies are mandatory to relate gut microbiota compositions and metabolic alterations.…”