核黄素缺乏(RD)诱导肝损伤,胚胎发育异常,和高死亡率。我们假设表型可以通过抑制ER应激来挽救。本研究的目的是使用体外和体内模型研究RD诱导的胚胎缺陷的潜在分子机制。用ER应激抑制剂(4-PBA)或CHOPsiRNA转染原代鸭胚肝细胞,并在RD培养基和核黄素充足(CON)培养基中培养8天。产鸭(n=20笼/饮食,1只鸟/笼)以RD饮食或CON饮食喂养14周,收集卵进行孵化。在孵化的第7天,将受精的RD卵在卵黄中注射或不注射4-PBA。与CON组相比,RD降低了细胞数量和细胞活力,诱导鸭胚肝细胞的氧化应激和凋亡。然而,在用ER应激抑制剂(4-PBA)或CHOPsiRNA转染后,RD肝细胞凋亡率分别下降60.6%和86.1%,分别,等于CON。这些结果表明RD诱导的肝细胞凋亡是由ER应激和CHOP途径介导的。在体内,RD胚胎显示出低孵化率,不正常的发展,肝损伤,ER压力,与CON组相比,细胞凋亡。然而,4-PBA管理,作为ER压力抑制的模型,RD组的胚胎发育基本恢复,肝脏损伤减轻,包括ER应激和细胞凋亡。值得注意的是,在4-PBA治疗后,RD组的孵化率从21.7%增加到72.7%,尽管仍低于CON组(87.7%)。这些结果表明ER应激-CHOP-凋亡途径是RD诱导的异常胚胎发育和死亡的分子机制。这一目标具有治疗或干预的潜力。
Riboflavin deficiency (RD) induces liver damage, abnormal embryonic development, and high mortality. We hypothesized that the phenotype could be rescued by inhibiting ER stress. The objectives of the present study were to investigate the underlying molecular mechanisms of RD-induced embryonic defects using in vitro and in vivo models. Primary duck embryonic hepatocytes were treated with an ER stress inhibitor (4-PBA) or transfected with CHOP siRNA, and cultured in RD medium and riboflavin-sufficient (CON) medium for 8 days. Laying ducks (n = 20 cages/diet, 1 bird/cage) were fed an RD diet or CON diet for 14 wk, and the eggs were collected for hatching. At day 7 of incubation, the fertilized RD eggs were injected with or without 4-PBA into the yolk. RD decreased cell number and cell viability compared to the CON group, induced oxidative stress and apoptosis in primary duck embryonic hepatocytes. However, after being treated with an ER stress inhibitor (4-PBA) or transfected with CHOP siRNA, the apoptosis rate in RD hepatocytes decreased by 60.6% and 86.1%, respectively, being equal to the CON. These results indicated that RD-induced hepatocyte apoptosis is mediated by ER stress and the CHOP pathway. In vivo, RD embryos showed low hatchability, abnormal development, liver damage, ER stress, and apoptosis compared to the CON group. However, 4-PBA administration, as a model of ER stress inhibition, substantially restored embryonic development and alleviated liver damage in the RD group, including ER stress and apoptosis. Notably, hatchability in the RD group increased from 21.7% to 72.7% after 4-PBA treatment, though it remained less than the CON group (87.7%). These results implicated ER stress-CHOP-apoptosis pathway as molecular mechanisms underlying RD-induced abnormal embryonic development and death, this target with potential for therapy or intervention.