Department of Gastroenterology, First Affiliated Hospital of Guangxi Medical University, Nanning, China.
Department of Gastroenterology, Second Affiliated Hospital of Guangxi Medical University, Nanning, China.
Braz J Med Biol Res. 2023 Jan 27;56:e12279. doi: 10.1590/1414-431X2023e12279. eCollection 2023.
Gelsolin (GSN) can sever actin filaments associated with autophagy. This study investigated how GSN-regulated actin filaments control autophagy in pancreatic ductal epithelial cells (PDECs) in acute pancreatitis (AP). AP was produced in a rat model and PDECs using caerulein (CAE). Rat pancreatic duct tissue and HPDE6-C7 cells were extracted at 6, 12, 24, and 48 h after CAE treatment. HPDE6-C7 cells in the presence of CAE were treated with cytochalasin B (CB) or silenced for GSN for 24 h. Pancreatic histopathology and serum amylase levels were analyzed. Cellular ultrastructure and autophagy in PDECs were observed by transmission electron microscopy after 24 h of CAE treatment. The expression of GSN and autophagy markers LC3, P62, and LAMP2 was evaluated in PDECs by immunohistochemistry and western blotting. Actin filaments were observed microscopically. Amylase levels were highest at 6 h of AP, and pancreatic tissue damage increased over time. Mitochondrial vacuolization and autophagy were observed in PDECs. CAE increased GSN expression in these cells over time, increased the LC3-II/LC3-I ratio and LAMP2 expression at 24 and 6 h of treatment, respectively, and decreased P62 expression at all time points. CB treatment for 24 h decreased the LC3-II/LC3-I ratio and LAMP2 expression, increased P62 levels, but had no impact on GSN expression in CAE-treated PDECs. CAE induced actin depolymerization, and CB potentiated this effect. GSN silencing increased the LC3-II/LC3-I ratio and LAMP2 expression and reduced actin depolymerization in CAE-treated PDECs. GSN may inhibit autophagosome biogenesis and autophagosome-lysosome fusion by increasing actin depolymerization in PDECs in AP.
肌动蛋白丝解聚蛋白（GSN）可切断与自噬相关的肌动蛋白丝。本研究旨在探讨 GSN 调节的肌动蛋白丝如何控制急性胰腺炎（AP）中胰腺导管上皮细胞（PDEC）中的自噬。通过给予蛙皮素（CAE）制备大鼠 AP 模型和 PDEC 模型。在 CAE 处理后 6、12、24 和 48 h 提取大鼠胰腺组织和 HPDE6-C7 细胞。用细胞松弛素 B（CB）或沉默 GSN 处理存在 CAE 的 HPDE6-C7 细胞 24 h。CAE 处理 24 h 后，通过透射电子显微镜观察胰腺导管上皮细胞的超微结构和自噬。通过免疫组织化学和蛋白质印迹法评估 CAE 处理后 24 h 时 PDEC 中 GSN 和自噬标志物 LC3、P62 和 LAMP2 的表达。观察肌动蛋白丝的显微镜。AP 时淀粉酶水平在 6 h 时最高，随着时间的推移，胰腺组织损伤增加。在 PDEC 中观察到线粒体空泡化和自噬。随着时间的推移，CAE 增加了这些细胞中的 GSN 表达，分别在 24 和 6 h 时增加了 LC3-II/LC3-I 比值和 LAMP2 表达，在所有时间点均降低了 P62 表达。CB 处理 24 h 降低了 LC3-II/LC3-I 比值和 LAMP2 表达，增加了 P62 水平，但对 CAE 处理的 PDEC 中 GSN 表达没有影响。CAE 诱导肌动蛋白解聚，CB 增强了这种作用。CAE 处理的 PDEC 中 GSN 沉默增加了 LC3-II/LC3-I 比值和 LAMP2 表达，并减少了肌动蛋白解聚。在 AP 中，GSN 可能通过增加 PDEC 中的肌动蛋白丝解聚来抑制自噬体生物发生和自噬体-溶酶体融合。
