Maselli Kathryn M, Levin Gabriel, Gee Kristin M, Leeflang Elisabeth J, Carreira Ana Claudia O, Sogayar Mari Cleide, Grikscheit Tracy C
Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA, 90027, USA.
Cell and Molecular Therapy Center (NUCEL), School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
Biochem Biophys Rep. 2021 Jan 4;25:100874. doi: 10.1016/j.bbrep.2020.100874. eCollection 2021 Mar.
R-spondins, including R-spondin 1 (RSPO1), are a family of Wnt ligands that help to activate the canonical Wnt/β-catenin pathway, which is critical for intestinal epithelial cell proliferation and maintenance of intestinal stem cells. This proliferation underpins the epithelial expansion, or intestinal adaptation (IA), that occurs following massive bowel resection and short bowel syndrome (SBS). The purpose of this study was to identify if recombinant human RSPO1 (rhRSPO1) could be serially administered to SBS zebrafish to enhance cellular proliferation and IA.
Adult male zebrafish were assigned to four groups: sham + PBS, SBS + PBS, sham + rhRSPO1, and SBS + rhRSPO1. Sham fish had a laparotomy alone. SBS fish had a laparotomy with distal intestinal ligation and creation of a proximal stoma. Fish were weighed at initial surgery and then weekly. rhRSPO1 was administered post-operatively following either a one- or two-week dosing schedule with either 3 or 5 intraperitoneal injections, respectively. Fish were harvested at 7 or 14 days with intestinal segments collected for analysis.
Repeated intraperitoneal injection of rhRSPO1 was feasible and well tolerated. At 7 days, intestinal epithelial proliferation was increased by rhRSPO1. At 14 days, SBS + rhRSPO1 fish lost significantly less weight than SBS + PBS fish. Measurements of intestinal surface area were not increased by rhRSPO1 administration but immunofluorescent staining for β-catenin and gene expression for was increased.
Intraperitoneal injection of rhRSPO1 decreased weight loss in SBS zebrafish with increased β-catenin + cells and expression at 14 days, indicating improved weight maintenance might result from increased activation of the canonical Wnt pathway.
R-spondins家族，包括R-spondin 1（RSPO1），是一类Wnt配体，有助于激活经典的Wnt/β-连环蛋白信号通路，该通路对肠道上皮细胞增殖和肠道干细胞的维持至关重要。这种增殖是肠道切除术后和短肠综合征（SBS）后发生的上皮扩张或肠道适应（IA）的基础。本研究的目的是确定重组人RSPO1（rhRSPO1）是否可以连续给予SBS斑马鱼，以增强细胞增殖和IA。
成年雄性斑马鱼分为四组：假手术+磷酸盐缓冲液（PBS）组、SBS+PBS组、假手术+rhRSPO1组和SBS+rhRSPO1组。假手术组仅进行剖腹手术。SBS组进行剖腹手术，同时结扎远端肠段并建立近端造口。在初次手术时对鱼称重，然后每周称重一次。rhRSPO1在术后分别按照1周或2周的给药方案进行给药，分别进行3次或5次腹腔注射。在7天或14天时收获鱼，收集肠段进行分析。
重复腹腔注射rhRSPO1是可行的，且耐受性良好。在7天时，rhRSPO1可增加肠道上皮增殖。在14天时，SBS+rhRSPO1组的鱼体重减轻明显少于SBS+PBS组。给予rhRSPO后，肠道表面积没有增加，但β-连环蛋白的免疫荧光染色和 的基因表达增加。
腹腔注射rhRSPO1可减少SBS斑马鱼的体重减轻，在14天时β-连环蛋白阳性细胞和 表达增加，表明经典Wnt信号通路激活增加可能导致体重维持改善。
