Li Shujue, Wu Wenqi, Wu Wenzheng, Duan Xiaolu, Kong Zhenzhen, Zeng Guohua
Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University. Guangdong Key Laboratory of Urology.
Kidney Blood Press Res. 2016;41(5):582-592. doi: 10.1159/000443455. Epub 2016 Aug 24.
BACKGROUND/AIMS: The interactions between calcium oxalate monohydrate (COM) crystals and renal tubular epithelial cells are important for renal stone formation but still unclear. This study aimed to investigate changes of epithelial cell phenotype after COM attachment and whether L-carnitine could protect cells against subsequent COM crystals adhesion.
Cultured MDCK cells were employed and E-cadherin and Vimentin were used as markers to estimate the differentiate state. AlexaFluor-488-tagged COM crystals were used in crystals adhesion experiment to distinguish from the previous COM attachment, and adhesive crystals were counted under fluorescence microscope, which were also dissolved and the calcium concentration was assessed by flame atomic absorption spectrophotometry.
Dedifferentiated MDCK cells induced by transforming growth factor β1 (TGF-β1) shown higher affinity to COM crystals. After exposure to COM for 48 hours, cell dedifferentiation were observed and more subsequent COM crystals could bind onto, mediated by Akt/GSK-3β/Snail signaling. L-carnitine attenuated this signaling, resulted in inhibition of cell dedifferentiation and reduction of subsequent COM crystals adhesion.
COM attachment promotes subsequent COM crystals adhesion, by inducing cell dedifferentiation via Akt/GSK-3β/Snail signaling. L-carnitine partially abolishes cell dedifferentiation and resists COM crystals adhesion. L-carnitine, may be used as a potential therapeutic strategy against recurrence of urolithiasis.
背景/目的：一水草酸钙（COM）晶体与肾小管上皮细胞之间的相互作用对肾结石形成很重要，但仍不清楚。本研究旨在探讨COM附着后上皮细胞表型的变化以及左旋肉碱是否能保护细胞免受随后COM晶体的黏附。
使用培养的MDCK细胞，以E-钙黏蛋白和波形蛋白作为标志物来评估分化状态。在晶体黏附实验中使用AlexaFluor-488标记的COM晶体以区别于先前的COM附着，在荧光显微镜下对黏附的晶体进行计数，这些晶体也被溶解并通过火焰原子吸收分光光度法评估钙浓度。
由转化生长因子β1（TGF-β1）诱导的去分化MDCK细胞对COM晶体表现出更高的亲和力。暴露于COM 48小时后，观察到细胞去分化，并且更多随后的COM晶体可以通过Akt/GSK-3β/蜗牛信号传导介导而黏附。左旋肉碱减弱了该信号传导，导致细胞去分化受到抑制以及随后COM晶体黏附减少。
COM附着通过Akt/GSK-3β/蜗牛信号传导诱导细胞去分化，从而促进随后COM晶体的黏附。左旋肉碱部分消除细胞去分化并抵抗COM晶体黏附。左旋肉碱可能用作预防尿石症复发的潜在治疗策略。
