Shámila Ismael, Catarina Rodrigues, Gilberto Maia Santos, Inês Castela, Inês Barreiros-Mota, Maria João Almeida, Conceição Calhau, Ana Faria, João Ricardo Araújo
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引用次数: 0
Abstract
Background/objectives: Indole-3-propionic acid (IPA) is a tryptophan-derived microbial metabolite that has been associated with protective effects against inflammatory and metabolic diseases. However, there is a lack of knowledge regarding the effects of IPA under physiological conditions and at the intestinal level.
Materials/methods: Human intestinal epithelial Caco-2 cells were treated for 2, 24, and/or 72 h with IPA or its precursors - indole, tryptophan, and propionate - at 1, 10, 100, 250, or 500 μM to assess cell viability, integrity, differentiation, and proliferation.
Results: IPA induced cell proliferation and this effect was associated with a higher expression of extracellular signal-regulated kinase 2 (ERK2) and a lower expression of c-Jun. Although indole and propionate also induced cell proliferation, this involved ERK2 and c-Jun independent mechanisms. On the other hand, both tryptophan and propionate increased cell integrity and reduced the expression of claudin-1, whereas propionate decreased cell differentiation.
Conclusions: In conclusion, these findings suggested that IPA and its precursors distinctly contribute to the proliferation, differentiation, and barrier function properties of human intestinal epithelial cells. Moreover, the pro-proliferative effect of IPA in intestinal epithelial cells was not explained by its precursors and is rather related to its whole chemical structure. Maintaining IPA at physiological levels, e.g., through IPA-producing commensal bacteria, may be important to preserve the integrity of the intestinal barrier and play an integral role in maintaining metabolic homeostasis.
期刊介绍:
Nutrition Research and Practice (NRP) is an official journal, jointly published by the Korean Nutrition Society and the Korean Society of Community Nutrition since 2007. The journal had been published quarterly at the initial stage and has been published bimonthly since 2010.
NRP aims to stimulate research and practice across diverse areas of human nutrition. The Journal publishes peer-reviewed original manuscripts on nutrition biochemistry and metabolism, community nutrition, nutrition and disease management, nutritional epidemiology, nutrition education, foodservice management in the following categories: Original Research Articles, Notes, Communications, and Reviews. Reviews will be received by the invitation of the editors only. Statements made and opinions expressed in the manuscripts published in this Journal represent the views of authors and do not necessarily reflect the opinion of the Societies.