Lipidomic Signatures in Feline Disease: A PRISMA-Guided Systematic Review

Background/Objectives: Lipidomics has become a key component of systems biology, enabling comprehensive characterisation of lipid species and their roles in health and disease. As regulators of membrane architecture, energy balance, inflammation, and cellular signalling, lipids offer a powerful framework for understanding metabolic dysfunction. In veterinary medicine, however, lipidomics remains comparatively underdeveloped. In cats, lipid metabolism is central to disorders such as hepatic lipidosis, cystitis, obesity, diabetes mellitus, and chronic inflammatory enteropathies, yet available data remain limited. This systematic review synthesised current evidence on lipidomics and lipid-focused profiling in feline disease and identified lipid alterations with potential clinical relevance. Methods: Following PRISMA 2020 guidelines, PubMed, ScienceDirect, and Scopus were searched for original studies (1994-2026) evaluating lipidomics or lipid-focused profiling in cats. Eligible studies assessed lipid species, fatty acids, lipid mediators, or lipoproteins in disease or physiological states. Owing to methodological heterogeneity, findings were synthesised narratively. Results: Seventeen studies met inclusion criteria, covering hepatic, urinary, gastrointestinal, renal, neurological, oncological, metabolic, and pharmacologically modulated conditions. Recurring alterations involved lipoproteins, triglycerides, phospholipids, sphingolipids, fatty acids, and oxylipins. More consistent patterns emerged in hepatic lipidosis, where lipoprotein disturbances may aid diagnosis; in lower urinary tract disease, where PUFA-derived oxylipins differentiated bacterial from idiopathic cystitis; and in obesity, where phospholipid and triglyceride shifts reflected metabolic risk. Fatty acid remodelling in chronic enteropathies aligned with mucosal inflammation, while sphingolipid changes in neurological disease correlated with severity. Heterogeneity in analytical platforms, dietary control, and study design limited comparability. Conclusions: Feline lipidomics reveals biologically meaningful alterations with emerging diagnostic and prognostic value. Although still developing, lipid-focused approaches may enhance disease characterisation and support translational research. Larger, standardised studies and robust reference datasets are needed to validate lipid signatures for clinical implementation.