Department of Surgery, Section of Pediatric Surgery, Indiana University School of Medicine, Indianapolis, IN, USA.
Indiana Center for Regenerative Medicine and Engineering, Indiana University School of Medicine, Indianapolis, IN, USA.
Pediatr Surg Int. 2022 Dec;38(12):1971-1979. doi: 10.1007/s00383-022-05257-1. Epub 2022 Oct 8.
Preterm infants are more susceptible to necrotizing enterocolitis (NEC) than term Queryinfants. This may be due to a relative paucity of Lgr5 or Bmi1-expressing intestinal stem cells (ISCs) which are responsible for promoting intestinal recovery after injury. We hypothesized that the cellular markers of Lgr5 and Bmi1, which represent the two distinct ISC populations, would be lower in younger mice compared to older mice. In addition, we hypothesized that experimental NEC would result in a greater loss of Lgr5 expression compared to Bmi1 expression.
Transgenic mice with EGFP-labeled Lgr5 underwent euthanasia at 10 different time points from E15 to P56 (n = 8-11/group). Lgr5-expressing ISCs were quantified by GFP ELISA and Bmi1 was assessed by qPCR. In addition, Lgr5 mice underwent experimental NEC via formula feeding and hypoxic and hypothermic stress. Additional portions of the intestine underwent immunostaining with anti-GFP or anti-Bmi1 antibodies to confirm ELISA and PCR results. For statistical analysis, p < 0.05 was significant.
Lgr5 and Bmi1expression was lowest in embryonal and early postnatal mice and increased with age in all segments of the intestine. Experimental NEC was associated with loss of Lgr5-expressing ISCs but no significant change in Bmi1 expression.
Lgr5 and Bmi1 expression increase with age. Lgr5-expressing ISCs are lower following experimental necrotizing enterocolitis while Bmi1 expression remains relatively unchanged. Developing a targeted medical therapy to protect the low population of ISCs in preterm infants may promote tissue recovery and regeneration after injury from NEC.
早产儿比足月儿更容易患坏死性小肠结肠炎（NEC）。这可能是由于 Lgr5 或 Bmi1 表达的肠干细胞（ISC）相对较少，而这些细胞负责促进损伤后的肠道恢复。我们假设，代表两种不同 ISC 群体的 Lgr5 和 Bmi1 的细胞标志物在较年轻的小鼠中会低于较年长的小鼠。此外，我们假设实验性 NEC 会导致 Lgr5 表达的丧失大于 Bmi1 表达的丧失。
具有 EGFP 标记的 Lgr5 的转基因小鼠在从 E15 到 P56 的 10 个不同时间点进行安乐死（n = 8-11/组）。通过 GFP ELISA 定量 Lgr5 表达的 ISC，并通过 qPCR 评估 Bmi1。此外，Lgr5 小鼠通过配方喂养、缺氧和低体温应激经历实验性 NEC。对肠道的其他部分进行免疫染色，用抗 GFP 或抗 Bmi1 抗体证实 ELISA 和 PCR 结果。统计分析中，p < 0.05 有统计学意义。
Lgr5 和 Bmi1 的表达在胚胎期和出生后早期的小鼠中最低，并且在所有肠段中随年龄增加而增加。实验性 NEC 与 Lgr5 表达的 ISC 丧失有关，但 Bmi1 表达没有明显变化。
Lgr5 和 Bmi1 的表达随年龄增加而增加。实验性 NEC 后 Lgr5 表达的 ISC 降低，而 Bmi1 表达相对不变。开发一种靶向医学疗法来保护早产儿中低数量的 ISC，可能会促进 NEC 损伤后的组织恢复和再生。
