二乙基亚硝胺诱导的大鼠肝癌前期病变肠道微生物组-短链脂肪酸代谢途径的动态变化及益生素干预效应

Dynamic changes of gut microbiome-short-chain fatty acid metabolic pathways in diethylnitrosamineinduced rat hepatocellular carcinoma preneoplastic lesions and the effect of probiotic intervention

目的 探讨二乙基亚硝胺(DEN)诱导的大鼠肝癌前期病变中肠道微生物组-短链脂肪酸代谢途径的动态变化,以及益生素干预的效应。方法 本研究选用雄性SD大鼠,通过一次性腹腔注射DEN诱导肝癌模型。实验分为对照组、DEN模型组和DEN模型干预组,后者自DEN注射次日起接受益生菌饮食干预。通过16S rRNA基因测序分析肠道菌群组成,采用气相色谱-质谱联用(GC-MS)检测粪便中的SCFA含量,并通过生化指标、组织病理学检测和分子生物学方法评估干预效果。结果 DEN模型组大鼠的体重增长显著缓慢(30±20 g),肝功能损害指标(ALT、AST、ALP、GGT)显著升高,与对照组(体重增长50±15 g;ALT 35±5 U/L,AST 30±4 U/L,ALP 90±10 U/L,GGT 20±3 U/L)和干预组(体重增长40±18 g;ALT 70±15 U/L,AST 65±10 U/L,ALP 150±20 U/L,GGT 45±8 U/L)相比有统计学差异。DEN模型组大鼠的HGF、TGF-β和α-SMA表达量显著高于对照组和干预组。肠道菌群分析显示,DEN模型组的Chao1和Shannon指数显著低于对照组和干预组。SCFA分析结果表明,DEN模型组大鼠的丙酸(0.52±0.19 mmol/L)和异戊酸(0.36±0.054 mmol/L)含量显著降低,而在DEN模型干预组中丙酸(0.80±0.21 mmol/L)和异戊酸(0.64±0.19 mmol/L)含量较DEN模型组显著恢复。结论 DEN诱导的大鼠肝癌模型中,肠道微生物组结构和SCFA代谢途径发生显著变化,益生素干预可以改善肠道微生物组成,增加SCFA产量,减轻肝脏损伤,对抗肝脏纤维化和肿瘤发展。这些发现为利用肠道微生物组和SCFA代谢途径预防和治疗肝癌提供了新的视角。

Objective To explore the dynamic changes of intestinal microbiome-short-chain fatty acid metabolic pathways in diethylnitrosamine(DEN)-induced liver precancerous lesions in rats and the effect of probiotic intervention.Methods Male SD rats were used in this study,and the liver cancer model was induced by a one-time intraperitoneal injection of DEN.The experiment was divided into a control group,a DEN model group and a DEN model intervention group,with the latter receiving probiotic dietary intervention starting from the day after DEN injection.The composition of intestinal flora was analyzed by 16S rRNA gene sequencing,the SCFA content in feces was detected by gas chromatography-mass spectrometry(GC-MS),and the intervention effect was evaluated by biochemical indicators,histopathological testing and molecular biology methods.Results The weight growth of the rats in the DEN model group was significantly slower(30±20 g),and the liver function damage indicators(ALT,AST,ALP,GGT)were significantly increased.Compared with the control group(weight gain 50±15 g;ALT 35±5 U/L,AST 30±4 U/L,ALP 90±10 U/L,GGT 20±3 U/L)and the intervention group(weight gain 40±18 g;ALT 70±15 U/L,AST There was a statistical difference compared with 65±10 U/L,ALP 150±20 U/L,GGT 45±8 U/L).The expression levels of HGF,TGF-βandα-SMA in rats in the DEN model group were significantly higher than those in the control group and intervention group.Intestinal flora analysis showed that the Chao1 and Shannon index of the DEN model group were significantly lower than those of the control group and intervention group.SCFA analysis results showed that the contents of propionic acid(0.52±0.19 mmol/L)and isovaleric acid(0.36±0.054 mmol/L)in rats in the DEN model group were significantly reduced,while in the DEN model intervention group,the contents of propionic acid were significantly reduced.The contents of isovaleric acid(0.80±0.21 mmol/L)and isovaleric acid(0.64±0.19 mmol/L)were significantly restored compared with the DEN model group.Conclusion In the DEN-induced rat liver cancer model,the intestinal microbiome structure and SCFA metabolic pathways undergo significant changes.Prebiotic intervention can improve the intestinal microbial composition,increase SCFA production,reduce liver damage,and combat liver fibrosis and tumor development.These findings provide a new perspective on using the gut microbiome and SCFA metabolic pathways to prevent and treat liver cancer.