The level of markers of apoptosis and cell proliferation in the area of restenosis after lower extremity arterial reconstruction

Aim. To assess the number of markers of apoptosis and cell proliferation, as well as their relationships in the area of restenosis of arterial reconstructions.

Methods. The study included 14 patients with a diagnosis of “arteriosclerosis obliterans of the lower extremities. Post-thrombotic occlusion of femoropopliteal bypass”. All patients were males with stage III disease according to the Fontaine classification modified by A.V. Pokrovsky. The average age of the patients was 65±3.4 years. The mean disease duration was 9±2.5 months after the initial intervention. Intraoperative material — distal anastomosis of femoropopliteal bypass — was taken from patients during arterial reconstructions. As a control, we used arterial wall samples obtained at organ procurement from postmortem donors without arteriosclerosis obliterans of the lower extremities. The number of samples is 8. The site of their collection is the popliteal artery. After sampling, they were crushed, and a homogenate was prepared, followed by the determination of the amount of p53, PDGF BB, Bcl2, and Bax proteins using the enzyme immunoassay. Statistical analysis was performed using the Statistica 10.0 software. Group differences were assessed by using the Mann–Whitney test. Correlation coefficients were determined using the Spearman test. Data are presented as medians and interquartile ranges.

Results. In tissue samples of restenosis, the amount of p53 protein was 0.07 units/mg and was significantly reduced compared with the control samples — 0.14 units/mg (р=0,015). The amount of platelet-derived growth factor PDGF BB was 0.17 ng/mg (р=0.05), Bcl2 — 1.61 ng/mg (р=0.008), Bax — 6.0 ng/mg (р=0.25) in the restenosis area and was increased in comparison with the control samples (0.04 ng/mg, 0.9 ng/mg, 4.4 ng/mg, respectively). A relationship between p53 and platelet-derived growth factor BB (r=–0.724, p=0.002), platelet-derived growth factor BB and Bcl2 (r=0.672, p=0.003) was revealed in samples from restenosis tissue obtained during arterial reconstructions.

Conclusion. The decreased apoptosis, expressed in a low level of p53 protein, with an increased Bax/Bcl-2 ratio is associated with an increase in the proliferative response of vascular wall cells in the area of restenosis of arterial reconstruction.