Abstract：
BACKGROUND: Carnivorous fish have a low carbohydrate utilization ability, and the physiological and molecular basis of glucose intolerance has not been fully illustrated.
OBJECTIVE: This study aimed to use largemouth bass as a model to investigate the possible mechanism of glucose intolerance in carnivorous fish with the help of snRNA-seq.
METHODS: Two diets were formulated, a low carbohydrate diet (LC) and a high carbohydrate diet (HC). The feeding trial lasted for six weeks, then growth performance, biochemical parameters, liver histology, and snRNA-seq were performed.
RESULTS: Growth performance of fish was not affected by the HC diet, while liver glucolipid metabolism disorder and liver injury were observed. A total of 13247 and 12848 cells from the liver derived from two groups were isolated and sequenced, and 7 major liver cell types were annotated by the marker genes. Hepatocytes and cholangiocytes were lower, hepatic stellate cells (HSCs) and immune cells were higher in the HC group compared to the LC group. Re-clustering analysis identified 7 subtypes of hepatocytes and immune cells, respectively. The HSCs showed more cell communication with other cell types, and periportal hepatocytes showed more cell communication with other subtype hepatocytes. Cell-cell communication mainly focused on cell junction related signaling pathways. Uncovered by the pseudotime analysis, midzonal hepatocytes were differentiated into two major branches, biliary epithelial hepatocytes, and hepatobiliary hybrid progenitor. Cell junction and liver fibrosis related genes were highly expressed in HC group, HC diet induced the activation of HSCs, and therefore led to the liver fibrosis of largemouth bass.
CONCLUSIONS: HC diet induced liver glucolipid metabolism disorder and liver injury of largemouth bass，the increase and activation of HSCs might be the main reason for the liver injury. In adaption to HC diet, midzonal hepatocytes differentiated into two major branches, biliary epithelial hepatocytes, and hepatobiliary hybrid progenitors.
OBJECTIVE: This study aimed to use largemouth bass as a model to investigate the possible mechanism of glucose intolerance in carnivorous fish with the help of snRNA-seq.
METHODS: Two diets were formulated, a low carbohydrate diet (LC) and a high carbohydrate diet (HC). The feeding trial lasted for six weeks, then growth performance, biochemical parameters, liver histology, and snRNA-seq were performed.
RESULTS: Growth performance of fish was not affected by the HC diet, while liver glucolipid metabolism disorder and liver injury were observed. A total of 13247 and 12848 cells from the liver derived from two groups were isolated and sequenced, and 7 major liver cell types were annotated by the marker genes. Hepatocytes and cholangiocytes were lower, hepatic stellate cells (HSCs) and immune cells were higher in the HC group compared to the LC group. Re-clustering analysis identified 7 subtypes of hepatocytes and immune cells, respectively. The HSCs showed more cell communication with other cell types, and periportal hepatocytes showed more cell communication with other subtype hepatocytes. Cell-cell communication mainly focused on cell junction related signaling pathways. Uncovered by the pseudotime analysis, midzonal hepatocytes were differentiated into two major branches, biliary epithelial hepatocytes, and hepatobiliary hybrid progenitor. Cell junction and liver fibrosis related genes were highly expressed in HC group, HC diet induced the activation of HSCs, and therefore led to the liver fibrosis of largemouth bass.
CONCLUSIONS: HC diet induced liver glucolipid metabolism disorder and liver injury of largemouth bass，the increase and activation of HSCs might be the main reason for the liver injury. In adaption to HC diet, midzonal hepatocytes differentiated into two major branches, biliary epithelial hepatocytes, and hepatobiliary hybrid progenitors.
摘要：
背景：食肉鱼的碳水化合物利用能力较低，葡萄糖不耐受的生理和分子基础尚未完全阐明。
目的：本研究以大口鲈鱼为模型，借助snRNA-seq研究食肉鱼类葡萄糖耐受不良的可能机制。
方法：配制两种饮食，低碳水化合物饮食（LC）和高碳水化合物饮食（HC）。喂养试验持续了六个星期,然后是增长业绩，生化参数，肝脏组织学,和snRNA-seq进行。
结果：鱼的生长性能不受HC日粮的影响，观察肝脏糖脂代谢紊乱和肝损伤。分离并测序两组肝脏来源的13247和12848细胞，标记基因注释了7种主要的肝细胞类型。肝细胞和胆管细胞较低，与LC组相比，HC组的肝星状细胞（HSC）和免疫细胞更高。重新聚类分析确定了7个亚型的肝细胞和免疫细胞，分别。HSC显示与其他细胞类型的细胞通讯，门静脉周围肝细胞与其他亚型肝细胞表现出更多的细胞通讯。细胞间的通讯主要集中在细胞连接相关的信号通路上。被伪时间分析发现，中带肝细胞分化成两个主要分支，胆管上皮肝细胞，和肝胆混合祖细胞。HC组细胞连接和肝纤维化相关基因高表达,HC饮食诱导HSC活化，因此导致了大口鲈鱼的肝纤维化。
结论：HC饮食诱导肝脏糖脂代谢紊乱和大口鲈鱼肝损伤，HSCs的增加和活化可能是肝损伤的主要原因。为了适应HC饮食，中带肝细胞分化成两个主要分支，胆管上皮肝细胞，和肝胆杂种祖细胞。
目的：本研究以大口鲈鱼为模型，借助snRNA-seq研究食肉鱼类葡萄糖耐受不良的可能机制。
方法：配制两种饮食，低碳水化合物饮食（LC）和高碳水化合物饮食（HC）。喂养试验持续了六个星期,然后是增长业绩，生化参数，肝脏组织学,和snRNA-seq进行。
结果：鱼的生长性能不受HC日粮的影响，观察肝脏糖脂代谢紊乱和肝损伤。分离并测序两组肝脏来源的13247和12848细胞，标记基因注释了7种主要的肝细胞类型。肝细胞和胆管细胞较低，与LC组相比，HC组的肝星状细胞（HSC）和免疫细胞更高。重新聚类分析确定了7个亚型的肝细胞和免疫细胞，分别。HSC显示与其他细胞类型的细胞通讯，门静脉周围肝细胞与其他亚型肝细胞表现出更多的细胞通讯。细胞间的通讯主要集中在细胞连接相关的信号通路上。被伪时间分析发现，中带肝细胞分化成两个主要分支，胆管上皮肝细胞，和肝胆混合祖细胞。HC组细胞连接和肝纤维化相关基因高表达,HC饮食诱导HSC活化，因此导致了大口鲈鱼的肝纤维化。
结论：HC饮食诱导肝脏糖脂代谢紊乱和大口鲈鱼肝损伤，HSCs的增加和活化可能是肝损伤的主要原因。为了适应HC饮食，中带肝细胞分化成两个主要分支，胆管上皮肝细胞，和肝胆杂种祖细胞。
