Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio.
Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania.
Am J Physiol Gastrointest Liver Physiol. 2020 May 1;318(5):G955-G965. doi: 10.1152/ajpgi.00349.2019. Epub 2020 Mar 23.
Functional fermentable fibers are considered essential for a healthy diet. Recently, we demonstrated that gut microbiota dysbiotic mice fed an inulin-containing diet (ICD) developed hepatocellular carcinoma (HCC) within 6 mo. In particular, a subset of Toll-like receptor 5-deficient (T5KO) mice prone to HCC exhibited rapid onset of hyperbilirubinemia (HB) and cholemia; these symptoms provide rationale that ICD induces cholestasis. Our objective in the present study was to determine whether inulin-fed T5KO-HB mice exhibit other known consequences of cholestasis, including essential fatty acid and fat-soluble vitamin deficiencies. Here, we measured hepatic fatty acids and serum vitamin A and D levels from wild-type (WT), T5KO low bilirubin (LB) and T5KO-HB mice fed ICD for 4 wk. Additionally, hepatic RNAseq and proteomics were performed to ascertain other metabolic alterations. Compared with WT and T5KO-LB, T5KO-HB mice exhibited steatorrhea, i.e., ~50% increase in fecal lipids. This could contribute to the significant reduction of linoleate in hepatic neutral lipids in T5KO-HB mice. Additionally, serum vitamins A and D were ~50% reduced in T5KO-HB mice, which was associated with metabolic compromises. Overall, our study highlights that fermentable fiber-induced cholestasis is further characterized by depletion of macro-and micronutrients. Feeding a dietary, fermentable fiber diet to a subset of Toll-like receptor 5 deficient (T5KO) mice induces early onset hyperbilirubinemia and cholemia that later manifests to hepatocellular carcinoma (HCC). Our study highlights that fermentable fiber-induced cholestasis is characterized with modest macro- and micronutrient deficiencies that may further contribute to hepatic biliary disease. Compared with chemical induction, immunization, surgery, or genetic manipulation, these findings provide a novel approach to study the cholestatic subtype of HCC.
功能性可发酵纤维被认为是健康饮食的重要组成部分。最近,我们证明,喂食含菊粉饮食(ICD)的肠道微生物失调小鼠在 6 个月内发展为肝细胞癌(HCC)。特别是,一组易患 HCC 的 Toll 样受体 5 缺陷(T5KO)小鼠表现出快速出现高胆红素血症(HB)和胆血症;这些症状表明 ICD 诱导胆汁淤积。我们在本研究中的目的是确定喂食菊粉的 T5KO-HB 小鼠是否表现出其他已知的胆汁淤积后果,包括必需脂肪酸和脂溶性维生素缺乏。在这里,我们测量了喂食 ICD 4 周的野生型(WT)、T5KO 低胆红素(LB)和 T5KO-HB 小鼠的肝脂肪酸和血清维生素 A 和 D 水平。此外,进行了肝 RNAseq 和蛋白质组学分析以确定其他代谢变化。与 WT 和 T5KO-LB 相比,T5KO-HB 小鼠表现出脂肪泻,即粪便脂质增加约 50%。这可能导致 T5KO-HB 小鼠肝中性脂质中亚油酸含量显著减少。此外,T5KO-HB 小鼠的血清维生素 A 和 D 减少了约 50%,这与代谢受损有关。总的来说,我们的研究强调,可发酵纤维诱导的胆汁淤积进一步表现为宏量和微量营养素的消耗。喂食可发酵纤维饮食可诱导一小部分 Toll 样受体 5 缺陷(T5KO)小鼠早期出现高胆红素血症和胆血症,随后发展为肝细胞癌(HCC)。我们的研究强调,可发酵纤维诱导的胆汁淤积表现为轻微的宏量和微量营养素缺乏,这可能进一步导致肝胆管疾病。与化学诱导、免疫接种、手术或基因操作相比,这些发现为研究胆汁淤积型 HCC 提供了一种新方法。