Adenosine receptors expression in cardiac fibroblasts of patients with left ventricular dysfunction due to valvular disease

Context: Adenosine restores tissue homeostasis through the interaction with its membrane receptors (AR) expressed on fibroblasts, endothelial cells, smooth muscle cells and leukocytes, but their modulation is still not fully understood.

Objective: To evaluate whether changes in the transcriptomic profiling of adenosine receptors (AR) occur in cardiac fibroblasts (CF) of patients (pts) with LV dysfunction due to valvular disease (V). The secondary aim was to compare in the same pts the results obtained at cardiac level with those found in circulating leukocytes.

Materials and methods: Auricle fragments were excised from 13 pts during prosthetic implantation while blood samples were collected from pts (n?=?9) and from healthy subjects (C, n?=?7). In 7 pts cardiac biopsy and blood samples were taken simultaneously. A human CF atrial cell line (cc) was used as control.

Results: AR higher levels of mRNA expression were observed with real-time PCR in Vpts compared to C, both at cardiac (overexpression A₁R:98%, A_2AR:63%, A_2BR:87%, A₃R:85%, CD39:92%, CD73:93%) and at peripheral level (A₁R vs C: p?=?.0056; A_2AR vs C: p?=?.0173; A_2BR vs C: p?=?.0272; A₃R vs C: p?=?.855; CD39 vs C: p?=?.0001; CD73 vs C: p?=?.0091).

Conclusion: All AR subtypes were overexpressed in CF of Vpts. The same trends in AR expression at cardiac level was assessed on circulating leukocytes, thus opening a new road to minimally invasive studies of the adenosinergic system in cardiac patients.