Calcium reuptake related genes as a cardiac biomarker in dogs with chronic mitral valvular insufficiency.

Abstract

BACKGROUND: Gene expression linked to sarcoplasmic reticulum calcium reuptake (SRCR) is altered in humans and animals with heart failure. HYPOTHESIS: The expression of SRCR genes in peripheral blood cells have the potential to be cardiac biomarkers of heart failure in dogs with chronic mitral valvular insufficiency (CMVI). ANIMALS: Client-owned 15 healthy control dogs and 23 small breed dogs with CMVI classified by severity, based on the classification system determined by the international small animal cardiac heart council. METHODS: Prospective, controlled, observational study. The expression levels of SRCR genes (SERCA2alpha, PLN, and HAX-1) were evaluated in peripheral blood of dogs at different stages of CMVI via real-time reverse transcription polymerase chain reaction. RESULTS: The mRNA expression levels of PLN and HAX-1, but not SERCA2alpha were significantly (P=.08), reduced in dogs with moderate to severe CMVI. The fold change in PLN expression compared with control were 0.38+/-0.07 (in group II) and 0.20+/-0.10 (in group III), while HAX-1 expression were 0.37+/-0.06 (group II) and 0.41+/-0.12 (group III). The expressions of PLN and HAX-1 were significantly reduced in groups II and III (P<.05) but not in group I (P>.05). The reduced PLN and HAX-1 expressions were highly correlated with the severity of heart failure (P<.001), vertebral heart score (P<.05), and left atrium to aortic root ratio (P<.05). CONCLUSIONS AND CLINICAL IMPORTANCE: PLN and HAX-1 can be potential biomarkers for heart failure caused by CMVI.