Abstract:
Glycogen storage disease type Ia (GSD-Ia) is caused by a deficiency in the glucose-6-phosphatase (G6Pase, G6pc) enzyme, which catalyses the final step of gluconeogenesis and glycogenolysis. Accumulation of G6pc can lead to an increase in glycogen and development of fatty liver. Ductular reactions refer to the proliferation of cholangiocytes and hepatic progenitors, which worsen fatty liver progress. To date, however, ductular reactions in GSD-Ia remain poorly understood. Here, we studied the development and potential underlying mechanism of ductular reactions in GSD-Ia in mice. We first generated GSD-Ia mice using CRISPR/Cas9 to target the exon 3 region of the G6pc gene. The typical GSD-Ia phenotype in G6pc -/- mice was then analysed using biochemical and histological assays. Ductular reactions in G6pc -/- mice were tested based on the expression of cholangiocytic markers cytokeratin 19 (CK19) and epithelial cell adhesion molecule (EpCAM). Yes-associated protein 1 (Yap) signalling activity was measured using western blot (WB) analysis and quantitative real-time polymerase chain reaction (qRT-PCR). Verteporfin was administered to the G6pc -/- mice to inhibit Yap signalling. The CRISPR/Cas9 system efficiently generated G6pc -/- mice, which exhibited typical GSD-Ia characteristics, including retarded growth, hypoglycaemia, and fatty liver disease. In addition, CK19- and EpCAM-positive cells as well as Yap signalling activity were increased in the livers of G6pc -/- mice. However, verteporfin treatment ameliorated ductular reactions and decreased Yap signalling activity. This study not only improves our understanding of GSD-Ia pathophysiology, but also highlights the potential of novel therapeutic approaches for GSD-Ia such as drug targeting of ductular reactions.
摘要:
糖原贮积病Ia型(GSD-Ia)是由葡萄糖-6-磷酸酶(G6Pase,G6pc)酶,催化糖异生和糖原分解的最后一步。G6pc的积累可导致糖原增加和脂肪肝的发展。导管反应是指胆管细胞和肝祖细胞的增殖,这加剧了脂肪肝的进展。迄今为止,然而,GSD-Ia中的导管反应仍然知之甚少。这里,我们研究了小鼠GSD-Ia导管反应的发展和潜在的潜在机制。我们首先使用CRISPR/Cas9靶向G6pc基因的外显子3区产生GSD-Ia小鼠。然后使用生化和组织学测定分析G6pc-/-小鼠中的典型GSD-Ia表型。根据胆管细胞标志物细胞角蛋白19(CK19)和上皮细胞粘附分子(EpCAM)的表达,测试了G6pc-/-小鼠的导管反应。使用蛋白质印迹(WB)分析和定量实时聚合酶链反应(qRT-PCR)测量Yes-相关蛋白1(Yap)信号传导活性。对G6pc-/-小鼠施用维替泊芬以抑制Yap信号传导。CRISPR/Cas9系统有效地产生了G6pc-/-小鼠,表现出典型的GSD-Ia特性,包括增长迟缓,低血糖,和脂肪肝。此外,CK19-和EpCAM-阳性细胞以及Yap信号传导活性在G6pc-/-小鼠的肝脏中增加。然而,维替泊芬治疗改善了导管反应并降低了Yap信号传导活性。这项研究不仅提高了我们对GSD-Ia病理生理学的理解,但也强调了GSD-Ia的新型治疗方法的潜力,例如针对导管反应的药物靶向。