Dose-Dependent Beneficial Effects of Tryptophan and Its Derived Metabolites on Akkermansia In Vitro: A Preliminary Prospective Study

Abstract

Akkermansia muciniphila, a potential probiotic, has been proven to lessen the effects of several diseases. As established, the relative abundance of Akkermansia is positively correlated with tryptophan metabolism. However, the reciprocal interaction between tryptophan and Akkemansia is still unclear. Herein, for the first time, the possible effects of tryptophan and its derived metabolites on A. muciniphila were preliminarily investigated, including growth, physiological function, and metabolism. Obtained results suggested that 0.4 g/L of tryptophan treatment could significantly promote the growth of A. muciniphila. Notably, when grown in BHI with 0.8 g/L of tryptophan, the hydrophobicity and adhesion of A. muciniphila were significantly improved, potentially due to the increase in the rate of cell division. Furthermore, A. muciniphila metabolized tryptophan to indole, indole-3-acetic acid, indole-3-carboxaldehyde, and indole-3-lactic acid. Indoles produced by gut microbiota could significantly promote the growth of A. muciniphila. These results could provide a valuable reference for future research on the relationship between tryptophan metabolism and A. muciniphila.

Ginkgo biloba extract ameliorates atherosclerosis via rebalancing gut flora and microbial metabolism

“…The microbiota‐derived metabolites are one of the most important functional readouts of intestinal microbiota. Due to the taxonomic enrichment of Akkermansia , Alloprevotella , Parabacteroides , Alistipes , and Desulfovibrionaceae in the GbE group, we then performed targeted metabolomic analysis on SCFAs, indole derivatives and bile acids, which have previously been reported to be related to these bacteria (Hong et al, 2021; Wang et al, 2019; Wang, Tian, Yu, Wang, & Zhu, 2019; Yin et al, 2021; Zhou, Xiao, Zhang, Zheng, & Deng, 2019). From the heatmap of the SCFAs profiles, we observed that the WD feeding led to an overall reduction in serum SCFAs levels, especially decreased the concentrations of formic acid, butyric acid, valeric acid, and hexanoic acid (Figure 6a).…”

“…Emerging studies have also reported Parabacteroides and Akkermansia could generate indole derivatives including IAA and ILA from dietary tryptophan (Russell et al, 2013; Yin et al, 2021), with IAM an important intermediate involved in the bacterial IAA synthesis pathway (Patten, Blakney, & Coulson, 2013). As expected, GbE intervention elevated the serum concentration of IAA, suggesting the stimulative effects on microbial IAA production.…”

“…The acids, which have previously been reported to be related to these bacteria (Hong et al, 2021;Wang, Tian, Yu, Wang, & Zhu, 2019;Yin et al, 2021;Zhou, Xiao, Zhang, Zheng, & Deng, 2019).…”

“…Emerging studies have also reported Parabacteroides and Akkermansia could generate indole derivatives including IAA and ILA from dietary tryptophan (Russell et al, 2013;Yin et al, 2021) The intestinal microbiota perturbations could affect the bile acids metabolic homeostasis, followed by the proatherogenic metabolic phenotypes. Clinical data exhibited lower circulating LCA level and fecal LCA excretion amounts in coronary heart disease patients (Charach et al, 2018;Duboc et al, 2012), implying that the loss of secondary bile acids caused by microbiota dysfunction might be a risk factor for atherosclerosis.…”

Pasteurized Akkermansia muciniphila Ameliorate the LPS-Induced Intestinal Barrier Dysfunction via Modulating AMPK and NF-κB through TLR2 in Caco-2 Cells

“…Dietary supplementation enriches the abundance of A. muciniphila in mice, such as the dark sweet cherry [3], alpine bearberry, lingonberry, and cloudberry extracts [4], and inulin [5], fucoidan [6], polysaccharides from Gastrodia elata and Ophiopogon japonicas [7,8]. In addition, tryptophan and its derived metabolites could significantly promote the growth of A. muciniphila in vitro [9].…”