Cakmak M, Yazıcı I, Boybeyi O, Ayva S, Aslan M K, Senyucel M F, Soyer T
Ankara University, Medical Faculty, Department of Pediatric Surgery, Ankara, Turkey.
Kırıkkale University, Medical Faculty, Department of Reconstructive Surgery, Kırıkkale, Turkey.
J Pediatr Urol. 2015 Oct;11(5):258.e1-6. doi: 10.1016/j.jpurol.2015.03.014. Epub 2015 Apr 24.
Autologous fat grafts are rich in adipose-derived stem cells, providing optimal soft-tissue replacement and significant quantities of angiogenic growth factor. Although fat grafts (FG) are used in several clinical conditions, the use of FG in urethral repairs and the effects of FG to urethral repairs have not yet been reported.
An experimental study was performed to evaluate the effect of FG on urethral angiogenesis and tissue growth factor (GF) levels.
Sixteen Wistar albino, adult, male rats were allocated into two groups: the control group (CG) (n = 8) and the experiment group (EG) (n = 8). After anesthetization of all rats, 3-mm vertical incisions were made on the urethras, and then sutured with interrupted 5/0 vicryl sutures. The operations were performed under a stereo dissecting microscope under magnification (×20). In the CG, no additional procedure was performed. In the EG after the same surgical procedure, 1 mm(3) FG was removed from the inguinal region by sharp dissection with a knife. The grafts were trimmed to 1 × 1 mm dimensions on millimeter paper. The FGs were placed on the repaired urethras. The skin was then closed. Samples from urethral and penile skin were taken 21 days after surgery in both groups. Density and intensity of staining with vascular-endothelial GF (VEGF), VEGF-receptor, and endothelial-GF receptor (EGFR) in the endothelial and mesenchymal cells of the penile urethral vessels were immunohistochemically evaluated. Data obtained from immunohistochemical evaluations were analyzed with SPSS 15.0. The P-values lower than 0.05 were considered as significant.
Density of VEGF staining was significantly decreased in the vascular endothelium of the EG compared to the CG (P < 0.05). Density of the EGFR staining was significantly decreased in the vascular endothelium of the EG compared to the CG (P < 0.05) (Table). Intensity of VEGF, VEGF-R and EGFR staining was not significantly different between the two groups. There were no significant differences between groups regarding to VEGFR staining and mesenchymal examination.
Decreased density was found in the VEGF staining in the vascular endothelium. This could be explained by the day that the tissues were harvested or because autologous fat grafts might cause decreased growth factor levels, which is contrary to the literature data.
Fat grafting has an immunohistochemical effect on the growth factor levels that are related to angiogenesis after urethral repair. It is difficult to make a firm conclusion about the role of fat grafting on urethral healing. Therefore, future studies are needed to see if FG can be used as an alternative to other procedures in order to avoid complications.
自体脂肪移植富含脂肪来源干细胞，能提供理想的软组织替代物以及大量血管生成生长因子。尽管脂肪移植已应用于多种临床情况，但脂肪移植在尿道修复中的应用及其对尿道修复的影响尚未见报道。
进行一项实验研究以评估脂肪移植对尿道血管生成及组织生长因子水平的影响。
将16只成年雄性Wistar白化大鼠分为两组：对照组（CG）（n = 8）和实验组（EG）（n = 8）。所有大鼠麻醉后，在尿道上作3毫米垂直切口，然后用5/0可吸收缝线间断缝合。手术在放大20倍的体视显微镜下进行。对照组不进行额外操作。实验组在相同手术操作后，用手术刀锐性分离从腹股沟区获取1立方毫米脂肪组织。将移植物在毫米纸上修剪成1×1毫米大小。把脂肪组织放置在修复后的尿道上。然后缝合皮肤。两组均在术后21天取尿道及阴茎皮肤样本。采用免疫组织化学方法评估阴茎尿道血管内皮细胞和间充质细胞中血管内皮生长因子（VEGF）、VEGF受体及内皮生长因子受体（EGFR）的染色密度和强度。用SPSS 15.0软件分析免疫组织化学评估获得的数据。P值小于0.05被认为具有统计学意义。
与对照组相比，实验组血管内皮中VEGF染色密度显著降低（P < 0.05）。与对照组相比，实验组血管内皮中EGFR染色密度显著降低（P < 0.05）（表）。两组间VEGF、VEGF-R及EGFR染色强度无显著差异。两组在VEGFR染色及间充质检查方面无显著差异。
发现血管内皮中VEGF染色密度降低。这可能是由于组织取材的时间，或者自体脂肪移植可能导致生长因子水平降低，这与文献数据相反。
脂肪移植对尿道修复后与血管生成相关生长因子水平具有免疫组织化学作用。关于脂肪移植在尿道愈合中的作用难以得出确切结论。因此，需要进一步研究以确定脂肪移植能否作为其他手术方法的替代方法以避免并发症。
