Departments of Surgery, Pathology, and Biomedical Sciences, School of Medicine and the Health Sciences, University of North Dakota, 1301 North Columbia Road, Stop 9037, Grand Forks, ND, 58202, USA.
Currently at Departments of Pharmaceutical Sciences and Biomedical Sciences-College of Pharmacy, Departments of Basic Sciences and Surgery-College of Medicine, California Northstate University, Elk Grove, CA, 95757, USA.
Hum Cell. 2019 Jul;32(3):240-250. doi: 10.1007/s13577-019-00247-3. Epub 2019 Mar 14.
Intestinal epithelial differentiation may be stimulated by diverse pathways including luminal short-chain fatty acids and repetitive mechanical deformation engendered by villous motility and peristalsis. Schlafen 12 (SLFN12) is a cytosolic protein that stimulates sucrase-isomaltase (SI) expression. We hypothesized that two disparate differentiating stimuli, butyrate and repetitive deformation, would each stimulate SLFN12 expression in human Caco-2 intestinal epithelial cells and that increased SLFN12 expression would contribute to the differentiating activity of the human Caco-2 intestinal epithelial cells. We stimulated Caco-2 cells with 1-2 mM butyrate or repetitive mechanical deformation at 10 cycles/min at an average 10% strain, and measured SLFN12 and SI expression by qRT-PCR. Sodium butyrate enhanced SLFN12 expression at both 1 mM and 2 mM although SI expression was only significantly increased at 2 mM. Repetitive deformation induced by cyclic mechanical strain also significantly increased both SLFN12 and SI gene expression. Reducing SLFN12 by siRNA decreased basal, deformation-stimulated, and butyrate-stimulated SLFN12 levels, compared to control cells treated with non-targeting siRNA, although both deformation and butyrate were still able to stimulate SLFN12 expression in siRNA-treated cells compared to control cells treated with the same siRNA. This attenuation of the increase in SLFN12 expression in response to mechanical strain or butyrate was accompanied by parallel attenuation of SI expression. Butyrate stimulated SI-promoter activity, and reducing SLFN12 by siRNA attenuated butyrate-induced SI-promoter activity. These data suggest that SLFN12 mediates at least in part the stimulation by both butyrate and repetitive mechanical deformation of sucrase-isomaltase, a late stage differentiation marker in human intestinal epithelial cells.
肠上皮细胞分化可能受多种途径刺激，包括腔短链脂肪酸和绒毛蠕动及蠕动产生的重复机械变形。Slafen 12（SLFN12）是一种刺激蔗糖酶-异麦芽糖酶（SI）表达的细胞质蛋白。我们假设两种不同的分化刺激物，即丁酸盐和重复变形，都会刺激人 Caco-2 肠上皮细胞中的 SLFN12 表达，并且增加的 SLFN12 表达将有助于人 Caco-2 肠上皮细胞的分化活性。我们用 1-2mM 丁酸钠或 10%平均应变 10 个循环/分钟的重复机械变形刺激 Caco-2 细胞，并通过 qRT-PCR 测量 SLFN12 和 SI 表达。虽然 SI 表达仅在 2mM 时显著增加，但 1mM 和 2mM 的丁酸钠均增强了 SLFN12 的表达。循环机械应变引起的重复变形也显著增加了 SLFN12 和 SI 基因表达。与用非靶向 siRNA 处理的对照细胞相比，用 siRNA 降低 SLFN12 表达降低了基础、变形刺激和丁酸盐刺激的 SLFN12 水平，尽管变形和丁酸盐仍能够刺激 siRNA 处理的细胞中的 SLFN12 表达与用相同 siRNA 处理的对照细胞相比。这种机械应变或丁酸盐刺激的 SLFN12 表达增加的衰减伴随着 SI 表达的平行衰减。丁酸钠刺激 SI 启动子活性，用 siRNA 降低 SLFN12 表达减弱了丁酸盐诱导的 SI 启动子活性。这些数据表明，SLFN12 至少部分介导了丁酸盐和重复机械变形对蔗糖酶-异麦芽糖酶的刺激，蔗糖酶-异麦芽糖酶是人类肠上皮细胞中晚期分化标志物。
