Increased blood mRNA expression of inflammatory and anti-fibrotic markers in dogs with congestive heart failure

Inflammation and extracellular matrix (ECM) remodeling contribute to the development of congestive heart failure (CHF), but the pathogenesis is still incompletely understood. Therefore, whole blood samples from eight dogs without cardiac disease and eight dogs with CHF were investigated for mRNA expression of IL1β, IL2, IL4, IL6, IL8, IL10, TNFα, IFNγ, TGFβ1-3, MMP1, -2, -3, -9 and TIMP1-4 using quantitative PCR.Dogs with CHF had significantly higher IL1β (P = 0.015), IL2 (P = 0.043), MMP1 (P = 0.031), TIMP3 (P = 0.012) and lower TNFα (P < 0.001), TGFβ3 (P = 0.006), TIMP1 (P = 0.015) and TIMP2 (P = 0.011) mRNA levels.Increased pro-inflammatory IL1β and anti-fibrotic MMP1 and reduced pro-fibrotic TGFβ and TIMP1 and TIMP2 in dogs with CHF suggest progressive left ventricular remodeling. The reduction of TNFα and increase of immunomodulatory IL2 and TIMP3 might suggest control of the inflammatory response. A better understanding of inflammation and ECM remodeling in cardiac diseases may lead to novel treatment approaches.