Abstract：
BACKGROUND: Diet can affect ammoniagenesis in cirrhosis and hepatic encephalopathy (HE), but the impact of dietary preferences on metabolomics in cirrhosis is unclear. As most Western populations follow meat-based diets, we aimed to determine the impact of substituting a single meat-based meal with an equal protein-containing vegan/vegetarian alternative on ammonia and metabolomics in outpatients with cirrhosis on a meat-based diet.
METHODS: Outpatients with cirrhosis with and without prior HE on a stable Western meat-based diet were randomized 1:1:1 into 3 groups. Patients were given a burger with 20 g protein of meat, vegan, or vegetarian. Blood for metabolomics via liquid chromatography-mass spectrometry and ammonia was drawn at baseline and hourly for 3 hours after meal while patients under observation. Stool microbiome characteristics, changes in ammonia, and metabolomics were compared between/within groups.
RESULTS: Stool microbiome composition was similar at baseline. Serum ammonia increased from baseline in the meat group but not the vegetarian or vegan group. Metabolites of branched chain and acylcarnitines decreased in the meat group compared with the non-meat groups. Alterations in lipid profile (higher sphingomyelins and lower lysophospholipids) were noted in the meat group when compared with the vegan and vegetarian groups.
CONCLUSIONS: Substitution of a single meat-based meal with a non-meat alternatives results in lower ammoniagenesis and altered serum metabolomics centered on branched-chain amino acids, acylcarnitines, lysophospholipids, and sphingomyelins in patients with cirrhosis regardless of HE or stool microbiome. Intermittent meat substitution with vegan or vegetarian alternatives could be helpful in reducing ammonia generation in cirrhosis.
METHODS: Outpatients with cirrhosis with and without prior HE on a stable Western meat-based diet were randomized 1:1:1 into 3 groups. Patients were given a burger with 20 g protein of meat, vegan, or vegetarian. Blood for metabolomics via liquid chromatography-mass spectrometry and ammonia was drawn at baseline and hourly for 3 hours after meal while patients under observation. Stool microbiome characteristics, changes in ammonia, and metabolomics were compared between/within groups.
RESULTS: Stool microbiome composition was similar at baseline. Serum ammonia increased from baseline in the meat group but not the vegetarian or vegan group. Metabolites of branched chain and acylcarnitines decreased in the meat group compared with the non-meat groups. Alterations in lipid profile (higher sphingomyelins and lower lysophospholipids) were noted in the meat group when compared with the vegan and vegetarian groups.
CONCLUSIONS: Substitution of a single meat-based meal with a non-meat alternatives results in lower ammoniagenesis and altered serum metabolomics centered on branched-chain amino acids, acylcarnitines, lysophospholipids, and sphingomyelins in patients with cirrhosis regardless of HE or stool microbiome. Intermittent meat substitution with vegan or vegetarian alternatives could be helpful in reducing ammonia generation in cirrhosis.
摘要：
背景：饮食可以影响肝硬化和肝性脑病（HE）的氨生成，但饮食偏好对肝硬化代谢组学的影响尚不清楚.由于大多数西方人口遵循肉类饮食，我们的目的是确定在以肉类为基础的肝硬化门诊患者中,用同样的含蛋白质的素食/素食替代方案代替单一肉类为基础的膳食对氨和代谢组学的影响.
方法：采用以西方肉类为基础的稳定饮食，患有和未患有HE的肝硬化门诊患者按1：1：1随机分为3组。患者被给予含有20克蛋白质肉的汉堡，素食主义者,或素食主义者。通过液相色谱-质谱法进行代谢组学的血液和氨在基线和餐后3小时每小时抽取，同时观察患者。粪便微生物组特征，氨的变化，和代谢组学在组间/组内进行比较。
结果：基线时粪便微生物组组成相似。肉类组的血清氨从基线增加，但素食或素食组没有增加。与非肉组相比，肉组中支链和酰基肉碱的代谢物减少。与素食主义者和素食主义者组相比，肉类组中的脂质分布发生变化（鞘磷脂较高，溶血磷脂较低）。
结论：用非肉类替代品替代单一肉类膳食导致更低的氨生成和以支链氨基酸为中心的血清代谢组学改变。酰基肉碱,溶血磷脂，无论HE或粪便微生物组如何，肝硬化患者的鞘磷脂和鞘磷脂。用素食或素食替代品间歇性替代肉类可能有助于减少肝硬化中的氨生成。
方法：采用以西方肉类为基础的稳定饮食，患有和未患有HE的肝硬化门诊患者按1：1：1随机分为3组。患者被给予含有20克蛋白质肉的汉堡，素食主义者,或素食主义者。通过液相色谱-质谱法进行代谢组学的血液和氨在基线和餐后3小时每小时抽取，同时观察患者。粪便微生物组特征，氨的变化，和代谢组学在组间/组内进行比较。
结果：基线时粪便微生物组组成相似。肉类组的血清氨从基线增加，但素食或素食组没有增加。与非肉组相比，肉组中支链和酰基肉碱的代谢物减少。与素食主义者和素食主义者组相比，肉类组中的脂质分布发生变化（鞘磷脂较高，溶血磷脂较低）。
结论：用非肉类替代品替代单一肉类膳食导致更低的氨生成和以支链氨基酸为中心的血清代谢组学改变。酰基肉碱,溶血磷脂，无论HE或粪便微生物组如何，肝硬化患者的鞘磷脂和鞘磷脂。用素食或素食替代品间歇性替代肉类可能有助于减少肝硬化中的氨生成。
