Dynamics of the level of transforming growth factors in blood serum in acute kidney injury in patients after coronary artery bypass grafting

Abstract

Acute kidney injury (AKI) is among most dangerous and common complications after oper-heart cardiosurgical operations. Therefore, a search is carried out for biological markers which could timely detect this condition. The article presents dynamics of TGF-β1, TGF-β2, TGF-β3 in blood serum prior and after a coronary artery bypass (CAB). The study included 120 patients with multivascular affection of coronary blood flow , and 50 conventionally healthy persons of similar age. The 1st group included 50 patients without evidence of AKI, the 2nd group consisted of 70 patients with AKI. Serum TGF-β1, TGF-β2, TGF-β3 was determined by ELISA technique in the main groups before (1) and after surgery (2) as well as on day 2 after operation (3), on day 7 after surgery (4), and once tested in the control group.. The results were expressed in ng/mL or pg/mL, as median values, upper and lower quartiles. Significance levels were determined by the Wilcoxon criterion. We have revealed dynamic changes of TGF-β levels in serum of the patients before and after CAB. Initially, before operation, we have found normal TGF-β1 levels and low TGF-β3 levels in the both main groups. Meanwhile, increased TGF-β2 levels are found only in the subgroup with subsequent AKI development. The dynamics of TGF-β1 showed a decrease just after surgery and 2 days later, being increased over initial level on day 7, and there were no significant differences for the groups with versus without complications. No dynamic differences were revealed for TGF-β2 in the patients of group 1 after surgery. Meanwhile, the group 2 after CAB displayed higher TGF-β2 values compared with controls during the entire follow-up period, neing, however, higher that in the group on the 2nd day following surgery. The TGF-β3 levels were increased just after surgery in both groups followed by subsequent decrease in group 1. In the 2nd group after CAB, the initial deficiency of TGF-β3 was changes in wave-like mode, over 2nd and 3rd period of monitoring. It was increased on day 7, becoming higher than in group1 but did not reach reference values. Further studies in the AKI group after CAB which depend on their severity and outcomes may detect new features of TGF-β system in the patients with this disorder.