Tourchi Ali, Kajbafzadeh Abdol-Mohammad, Ebadi Maryam, Tavangar Seyed Mohammad, Jarooghi Neda
Division of Pediatric Urology, Brady Urological Institute, The Johns Hopkins Medical Institutions, Baltimore, MD.
Department of Pediatric Urology, Pediatric Urology Research Center, Pediatric Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran.
Urology. 2014 Dec;84(6):1467-74. doi: 10.1016/j.urology.2014.08.021. Epub 2014 Oct 18.
To investigate the association between impaired autophagy in smooth muscle cells and the development of congenital ureteropelvic junction (UPJ) obstruction (UPJO).
Tissue specimens were obtained from 40 patients with unilateral UPJO and were divided into 3 sections as renal pelvis, site of obstruction, and the ureter distal to obstruction. Control specimens were obtained from the UPJ of 40 age-matched cadavers. Autophagy was evaluated by image analysis techniques for the expression of light chain 3 (LC3) after immunohistochemical staining of LC3 rabbit polyclonal antibody and Western blot analysis; additionally, myocyte apoptosis was determined using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, 4',6-diamidino-2-phenylindole staining, and p53 immunohistochemical staining. To assess the possible role of cell senescence, P21 and P16 immunohistochemistry staining was applied. Cellular proliferation was assessed by image analysis of proliferating cell nuclear antigen-stained specimens.
LC3 expression was significantly increased at the renal pelvis (P <.05). Apoptotic indices of smooth muscle cells and Bcl-2 were significantly greater at the site of UPJO (5.15 ± 0.91) compared with the UPJs of the control group (P <.001). A significant negative correlation was found between TUNEL and LC3 in all sections of the obstructed UPJ complex (P <.05). Proliferating cell nuclear antigen and LC3 were positively correlated in the renal pelvis and UPJ (P <.05); however, no specimen was stained for p16, p21, and p53.
In conclusion, impaired autophagy is associated with the development of congenital UPJO. Nonetheless, further studies are mandated to establish its etiologic role.
探讨平滑肌细胞自噬受损与先天性输尿管肾盂连接部（UPJ）梗阻（UPJO）发生发展之间的关联。
收集40例单侧UPJO患者的组织标本，并将其分为肾盂、梗阻部位及梗阻远端输尿管3部分。对照标本取自40例年龄匹配的尸体的UPJ。通过免疫组化染色兔抗LC3多克隆抗体及蛋白质免疫印迹分析后，采用图像分析技术评估自噬相关蛋白轻链3（LC3）的表达；此外，使用末端脱氧核苷酸转移酶dUTP缺口末端标记法（TUNEL）、4',6-二脒基-2-苯基吲哚染色及p53免疫组化染色来检测肌细胞凋亡情况。为评估细胞衰老的可能作用，采用P21和P16免疫组化染色。通过对增殖细胞核抗原染色标本进行图像分析来评估细胞增殖情况。
肾盂处LC3表达显著增加（P <.05）。与对照组的UPJ相比，UPJO部位平滑肌细胞凋亡指数及Bcl-2水平显著更高（5.15 ± 0.91）（P <.001）。在梗阻性UPJ复合体的所有部位，TUNEL与LC3之间均存在显著负相关（P <.05）。肾盂和UPJ处增殖细胞核抗原与LC3呈正相关（P <.05）；然而，未检测到p16、p21和p53的染色。
总之，自噬受损与先天性UPJO的发生发展相关。尽管如此，仍需进一步研究以明确其病因学作用。
