Analysis of serum proteomic in cats with polycystic kidney disease-1 gene mutation

Feline autosomal dominant polycystic kidney disease (PKD) is common in Persian and Persian-cross cats. This study aims to investigate proteins that can be potential biomarkers for early disease diagnosis in cats with PKD1 heterozygous gene mutations and compare them with chronic kidney disease cats and normal wild-type cats. Thirty-three client-owned cats of variable breeds (ten PKD1 gene mutation cats, twelve wild-type cats with normal blood profiles, and eleven wild-type cats with chronic renal disease) were enrolled in this study. This study used serum-based proteomic profiling analysis in cats. Abdominal ultrasounds were examined in all cats. Proteomic analysis was conducted by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and liquid chromatography-tandem mass spectrometry (LC-MS/MS). One hundred and fifty-nine proteins were significantly differentially expressed between each group. The proteins identified in this study are known to regulate the apoptosis pathway. The apoptosis regulator Bcl-2 (BCL2) was overexpressed in the chronic kidney disease (CKD) group, while apoptotic peptidase activating factor 1 (APAF1) and BCL2-associated X apoptosis regulator (BAX) were only expressed in the PKD group. Ingenuity pathway analysis revealed that proteins uniquely expressed in the PKD group were linked to the Wnt signaling pathway and MAPK pathway. Asparagine synthetase domain-containing and secreted frizzled-related proteins were interesting proteins that should be studied further for the possibility of a candidate protein for disease detection. The proteomic profiles identified in this study could be used as potential novel biomarkers for the early detection of PKD in cats.