Department of Food Science, Rutgers Center for Lipid Research, Institute of Food Nutrition and Health, Rutgers University, NJ, USA.
Department of Veterinary Pathobiology, University of Missouri Metagenomics Center, University of Missouri, MO, USA.
Biochim Biophys Acta Mol Cell Biol Lipids. 2022 May;1867(5):159122. doi: 10.1016/j.bbalip.2022.159122. Epub 2022 Feb 11.
Vitamin A deficiency (VAD) results in intestinal inflammation, increased redox stress and reactive oxygen species (ROS) levels, imbalanced inflammatory and immunomodulatory cytokines, compromised barrier function, and perturbations of the gut microbiome. To combat VAD dietary interventions with β-carotene, the most abundant precursor of vitamin A, are recommended. However, the impact of β-carotene on intestinal health during VAD has not been fully clarified, especially regarding the VAD-associated intestinal dysbiosis. Here we addressed this question by using LratRbp (vitamin A deficient) mice deprived of dietary preformed vitamin A and supplemented with β-carotene as the sole source of the vitamin, alongside with WT (vitamin A sufficient) mice. We found that dietary β-carotene impacted intestinal vitamin A status, barrier integrity and inflammation in both WT and LratRbp (vitamin A deficient) mice on the vitamin A-free diet. However, it did so to a greater extent under overt VAD. Dietary β-carotene also modified the taxonomic profile of the fecal microbiome, but only under VAD. Given the similarity of the VAD-associated intestinal phenotypes with those of several other disorders of the gut, collectively known as Inflammatory Bowel Disease (IBD) Syndrome, these findings are broadly relevant to the effort of developing diet-based intervention strategies to ameliorate intestinal pathological conditions.
维生素 A 缺乏症 (VAD) 可导致肠道炎症、氧化应激和活性氧 (ROS) 水平增加、炎症和免疫调节细胞因子失衡、屏障功能受损以及肠道微生物组紊乱。为了对抗 VAD，建议采用β-胡萝卜素等膳食干预措施，β-胡萝卜素是维生素 A 的最丰富前体。然而，β-胡萝卜素在 VAD 期间对肠道健康的影响尚未完全阐明，尤其是在 VAD 相关的肠道菌群失调方面。在这里，我们使用缺乏维生素 A 的 LratRbp（维生素 A 缺乏）小鼠和 WT（维生素 A 充足）小鼠作为研究对象，这些小鼠在无维生素 A 饮食中缺乏膳食预形成的维生素 A，并补充β-胡萝卜素作为维生素 A 的唯一来源，来解决这个问题。我们发现，在无维生素 A 饮食中，β-胡萝卜素会影响 WT 和 LratRbp（维生素 A 缺乏）小鼠的肠道维生素 A 状态、屏障完整性和炎症，但在明显的 VAD 下影响更大。β-胡萝卜素还改变了粪便微生物组的分类组成，但仅在 VAD 下如此。鉴于 VAD 相关的肠道表型与其他几种肠道疾病（统称为炎症性肠病综合征）相似，这些发现与开发基于饮食的干预策略以改善肠道病理状况的努力密切相关。
