Effects of stem cells and platelet rich fibrin on colonic anastomosis: Experimental study

Gastrointestinal system surgery occupies an important role in general surgery practice. Although the improvements in gastrointestinal surgery, anostomosis leakage is a major problem. The purpose of the many performed study is to decrease complications by providing a safe colon anastomosis. One of the target in anastomosis healing is increasing durability of anastomosis by increasing tissue perfussion. Platelet rich fibrin (PRF) is a 2nd generation platelet concentration that effects angionesis and wound healing by the included growth factors and cytokines. Adipose derived tissue stem cell is one of the most potential stem cells by the harvesting method and the potential to differenciate into multiple tissues. It‟s been shown in many studies that adipose dervied tissue stem cell can convert into new cells as increasing angiogenesis. In the performed study, 80 female Sprague-Dawley rats were used. Each three group consisted with 20 rat. Also 20 rat were used for harvesting stem cells and platelet rich fibrin. Decending colons were completely transected and anastomosis were performed in every group. No additional process is applied on anastomosis of the control group while platelet rich fibrin, platelet rich fibrin+stem cells were applied on anastomosis of other 2 groups respectively. All rats were sacrified by the 7th day of the experiment. All three groups had 2 subgroups. One subgroup was planned to measure the anastomotic bursting pressure and hystopathologic examination, second subgroup was planned for angiographic examination of the angiogenesis. Adipose tissue derived stem cells were examined with DiI under flourescent microscope immunohistochemically. There were no significant differences in weights of the rats between 3 groups. According to the beginning and end weights, there were no significant differences between the control group (p=0.253), PRF group (p<0,05) and the PRF + stem cell (p=0,525) group. Although intraabdominal adhesions were statistically high in the control group in comparison to PRF group and PRF+stem cell groups; there were no perforation, fistulation nor intraabdominal abcess in any group. When compared in anastomosis burst pressure and angiogenesis; signficant difference was observed between the PRF+stem cell group and other two groups. Mean bursting pressure was calculated as; 159,1 ± 18,2 mmHg in the vii control group, 176 ± 24,3 mmHg in PRF group, 191,1 ± 20,9 mmHg (p<0,05) in the PRF+stem cell group. Vessel per millimeter square was calculated in the angiographic examination. In the control group 17,7 ± 4,3; in the PRF group 25 ± 3,7 and in the PRF + stem cell group 33,9 ± 4,1 vessel (p<0,05) were counted. Reepithelialization (p=0.082), fibrozis (p=0,089), ischemic necrosis (p=0,058) and impairment in the muscular layer (p=0,133) were examined histopathologically and no significant difference was observed. But there were no significant difference in vascular proliferation (p<0,05) and inflammation (p<0,05) between the PRF and PRF + stem cell groups when compared to the control group. And there were no significant difference in the vascular proliferation (p=0,211) and inflammation (p=0,999) between PRF and PRF+stem cell groups. Stem cells were observed as transforming to endothelial cells and was seen among the villous components in the flourescent microscope examination. As a conclusion; PRF by secreting growth factors, stem cells by transforming to endothelial cells and secreting cytokines, effect anastomosis healing. Having no significant histopathologic difference in vascular proliferation and inflammation was attributed to growth hormones that reach peak level at 7th day and cytokine secretion of PRF. It is necessary to plan different studies to determine the exact mechanisms of PRF and stem cell on colonic anastomoses in longer time intervals. Key words: Trombosit rich fibrin, stem cell, colonic anastomosis