Effects of the amniotic membrane on healing of colonic anastomoses in experimental left-sided colonic obstruction

Effect of Acellular Amniotic Membrane Matrix Patch on Healing of Cut Surface After Sleeve Gastrectomy in Rats

Background: The aim of this study was to evaluate the effect of acellular amniotic membrane matrix patch on healing cut surface after sleeve gastrectomy in rats. Methods: Thirty male Wistar albino rats were divided into three groups: control (n = 10), Experiment-1 (n = 10), and Experiment-2 (n = 10) groups. Control group rats underwent only sleeve gastrectomy with primary gastrorrhaphy. Experiment-1 group rats underwent sleeve gastrectomy, primary gastrorrhaphy and covered with acellular amniotic membrane matrix patch. Experiment-2 group rats underwent sleeve gastrectomy, incomplete primary gastrorrhaphy and covered with acellular amniotic membrane matrix patch. All rats were sacrificed on the fifth postoperative day. Macroscopic findings and histopathologic alterations were evaluated and compared. Results: There was a statistically significant difference between levels of PMNs, granulation formation and vascularization, distributions of edema, type of mucosal epithelium, and fibroblastic proliferation according to groups (p < 0.05). The PMNs level in the Experiment-1 group was significantly lower than the control group (p < 0.05). In experiment groups, the level of granulation tissue, vascularization and fibroblastic proliferation was significantly higher than the control group (p < 0.05). The levels of edema and type of mucosal epithelium of the experiment groups were significantly lower than the control group (p < 0.05). Conclusion: Covering sleeve gastrectomy cut surface area with acellular amniotic membrane matrix results better healing. Moreover, acellular amniotic membrane matrix provides safe healing even in incomplete sutured area.

The effects of preservation procedures on amniotic membrane's ability to serve as a substrate for cultivation of endothelial cells

Amniotic membrane (AM) has been used as a scaffold for the ex vivo expansion of different types of cells and a cell delivery matrix in regenerative medicine. Since the preservation procedures can influence the AM properties for experimental and clinical purposes, this study was established to investigate the feasibility of using the AM after different preservation methods to serve as substrates for endothelial cell expansion ex vivo. The effects of cryopreservation and lyophilization were evaluated on mechanical and histological characteristics of the AM, and the results were compared with the fresh AM. The ECM components of the basement membrane were well conserved in all groups. Although lyophilization resulted in more histological changes and lower level of physical variables including thickness, F(max), elongation at break and suture retention than the fresh and cryopreserved AM, endothelial cells grown on the lyophilized AM were better attached to the basement membrane. Cytotoxicity assay by MTT showed that the lyophilized AM is a compatible substrate for endothelial cells cultivation. The findings of this study suggest that the lyophilized AM is a suitable matrix for cultivation of endothelial cells due to this fact that lyophilization led to exposure of basement membrane of the AM.