WNT4在辐射诱导的肠上皮再生中促进隐窝的对称分裂。

WNT4 promotes the symmetric fission of crypt in radiation-induced intestinal epithelial regeneration.

作者信息

Cheng Jingyang, Wu Haiyong, Cui Yanmei

机构信息

Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, Guangdong Institute of Gastroenterology, The Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People's Republic of China.

Biomedical Innovation Center, The Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People's Republic of China.

出版信息

Cell Mol Biol Lett. 2024 Dec 26;29(1):158. doi: 10.1186/s11658-024-00677-4.

DOI:10.1186/s11658-024-00677-4

PMID:39725925

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11670417/

Abstract

BACKGROUND

Radiotherapy for pelvic malignant tumors inevitably causes intestinal tissue damage. The regeneration of intestinal epithelium after radiation injury relies mainly on crypt fission. However, little is known about the regulatory mechanisms of crypt fission events.

METHODS

The effects of WNT4 on crypt regeneration and the symmetry of crypt fission were examined using a mouse small intestinal organoid culture model. Three-dimensional (3D) reconstructed images of organoids were applied to assess the symmetry of crypt fission and Paneth cell localization upon manipulation of WNT4 expression. The effect of WNT4 on the expression of β-catenin target genes was analyzed by real-time quantitative polymerase chain reaction (RT-qPCR). The in vivo effect of WNT4 overexpression mediated by adeno-associated virus (AAV) on symmetric fission of crypt was investigated using a radiation-injured mouse model.

RESULTS

WNT4 has a special function of promoting symmetric fission of small intestinal crypts, although it inhibits budding, stemness, and cell proliferation on organoids. WNT4 promotes the correct localization of Paneth cells in the crypt base by regulating the expression of EphB3, thereby promoting the symmetric fission of small intestinal crypts. WNT4 negatively regulates the canonical WNT/β-catenin signaling pathway, and it promotes symmetric crypt fission in a ROR2 receptor-dependent manner. Moreover, in patients and animal models of radiation-induced intestinal injury, we found that the regenerated crypts are irregular in size and shape, Paneth cells are mislocalized, and the expression of WNT4 is decreased while EphB3 is increased. Importantly, restoration of WNT4 expression mediated by AAV effectively promotes symmetric crypt fission and thus improves the regularity of regenerating crypts in mice with radiation-induced injury.

CONCLUSIONS

Our study highlights the critical role of WNT4 in the regulation of crypt fission and provides WNT4 as a potential therapeutic target for radiation enteritis.

摘要

背景

盆腔恶性肿瘤放疗不可避免地会导致肠组织损伤。辐射损伤后肠上皮的再生主要依赖于隐窝裂变。然而，关于隐窝裂变事件的调控机制知之甚少。

方法

使用小鼠小肠类器官培养模型研究WNT4对隐窝再生和隐窝裂变对称性的影响。应用类器官的三维（3D）重建图像评估在操纵WNT4表达时隐窝裂变的对称性和潘氏细胞定位。通过实时定量聚合酶链反应（RT-qPCR）分析WNT4对β-连环蛋白靶基因表达的影响。使用辐射损伤小鼠模型研究腺相关病毒（AAV）介导的WNT4过表达对隐窝对称裂变的体内作用。

结果

WNT4具有促进小肠隐窝对称裂变的特殊功能，尽管它抑制类器官的出芽、干性和细胞增殖。WNT4通过调节EphB3的表达促进潘氏细胞在隐窝底部的正确定位，从而促进小肠隐窝的对称裂变。WNT4负向调节经典WNT/β-连环蛋白信号通路，并以ROR2受体依赖性方式促进隐窝对称裂变。此外，在辐射诱导的肠损伤患者和动物模型中，我们发现再生的隐窝大小和形状不规则，潘氏细胞定位错误，WNT4表达降低而EphB3表达增加。重要的是，AAV介导的WNT4表达恢复有效地促进了隐窝对称裂变，从而改善了辐射损伤小鼠再生隐窝的规则性。