Local and Systemic Changes in Lipid Profile as Potential Biomarkers for Canine Atopic Dermatitis

Abstract

Lipids play a critical role in the skin as components of the epidermal barrier and as signaling and antimicrobial molecules. Atopic dermatitis in dogs is associated with changes in the lipid composition of the skin, but whether these precede or follow the onset of dermatitis is unclear. We applied rapid lipid-profiling mass spectrometry to skin and blood of 30 control and 30 atopic dogs. Marked differences in lipid profiles were observed between control, nonlesional, and lesional skin. The lipid composition of blood from control and atopic dogs was different, indicating systemic changes in lipid metabolism. Female and male dogs differed in the degree of changes in the skin and blood lipid profiles. Treatment with oclacitinib or lokivetmab ameliorated the skin condition and caused changes in skin and blood lipids. A set of lipid features of the skin was selected as a biomarker that classified samples as control or atopic dermatitis with 95% accuracy, whereas blood lipids discriminated between control and atopic dogs with 90% accuracy. These data suggest that canine atopic dermatitis is a systemic disease and support the use of rapid lipid profiling to identify novel biomarkers.

Feeding of fish oil and medium-chain triglycerides to canines impacts circulating structural and energetic lipids, endocannabinoids, and non-lipid metabolite profiles

“…Some publications examine non-serum matrices such as ocular fluids ( 60 ) or red blood cell membrane ( 65 ) and thus may not reflect circulating levels or include both structural and energetic lipids. Other publications have examined the impact of dietary oils on the circulating lipidome in dogs with inflammatory dermatological ( 64 ) or gastrointestinal ( 67 ) disease, and these disease states may perturb lipid metabolism relative to healthy canines of the sort enrolled in the current study. Some prior reports in this area of investigation have examined the changes in circulating lipid metabolites with LCPUFA and MCT feeding, but some of these studies did not include control foods (lacking both types of fats) or lacked a food that combined both fats ( 92 – 94 ).…”

“…Examinations of the lipidome have shown utility in studying genetic ( 63 ) and pharmacologic ( 54 ) canine models of disease. The canine lipidome has also been assessed in naturally occurring inflammatory diseases, including atopic dermatitis ( 64 ), chronic gastroenteritis ( 65 ), and the aforementioned endocrine diseases ( 55 ). The impact of dietary LCPUFA(n3), including DHA and EPA, on classes of metabolites within the canine lipidome has been reported ( 66 ), including a study that monitored the canine lipidome during a dietary feeding study with increased n6- and n3-PUFA in dogs with enteritis ( 67 ).…”

Sphingomyelin-Rich Lipid Extract Collar for Canine Atopic Dermatitis

“…These interventions have shown some positive effects on skin health, and they are normally delivered in the form of a spot-on or a shampoo presentation. Incorporating a LE into a polymer matrix and applying this in a collar presentation represents a new approach to acting on skin lipids [ 12 ], and as a more user-friendly way of managing CAD patients. The results described in the in vivo test in CAD dogs support the efficacy and safety of such a LE collar.…”

“…Epidermal barrier dysfunction plays a key role in the pathogenesis of CAD, as it allows microbial adherence, penetration of allergenic proteins, and may trigger inflammatory and allergic responses. That is why one of the targets of topical therapy in CAD patients is to restore epidermal barrier integrity and function [ 1 , 3 , 8 , 9 , 10 , 11 , 12 ]. Currently, the management of the atopic canine patient includes restoration of the skin barrier function by, for instance, applying sphingolipids and fatty acid emulsions [ 2 , 13 ].…”

The Future of Biomarkers in Veterinary Medicine: Emerging Approaches and Associated Challenges

“…MRM-profiling has been used to detect changes in the lipid composition of the epidermis in atopic dogs even when the skin seems clinically healthy, and sex is a modifying factor in the lipid profile of canine atopic dermatitis [ 123 ]. This study contributes to a better understanding of epidermal lipid alterations with the development of atopic dermatitis and as the chronic inflammatory process progresses.…”