Numerous commensal bacteria present in the gut microbiota produce short chain fatty acids (SCFA’s) particularly acetate, butyrate and propionate. These SCFA’s have been associated with several biological effects upon host. Growing evidence suggests that specific microbes such as Faecalibacterium prausnitzii and Akkermansia muciniphila have favorable effects on intestinal inflammation and obesity, respectively (Sokol et al. PNAS 2008, Everard et al. PNAS 2013). However, the direct implication of these microbes on intestinal transcriptional response is unknown.

 

Bright-field images of mouse small-intestinal organoids cultured in Matrigel for 1 (A), 3 (B), and 7 (C) days after splitting. Lukovac S et al. doi:10.1128/mBio.01438-14

Bright-field images of mouse small-intestinal organoids cultured in Matrigel for 1 (A), 3 (B), and 7 (C) days after splitting. Lukovac S et al. doi:10.1128/mBio.01438-14

 

Using an elegant model of intestinal organoids, Sabina Lukovac, Clara Belzer and colleagues have demonstrated that despite the fact that A. muciniphila and F. prausnitzii are both considered as beneficial microbes impacting on intestinal barrier they differently affect transcriptional response of organoids upon exposure of SCFAs and products generated by these two specific microbes.
In this study published in mBIO (Lukovac, Belzer et al. mBIO August 2014) the authors found that A. muciniphila affects the expression of several genes involved in host lipid metabolism (i.e., FIAF, GPR43, PPARg) and epigenetic or silencing of gene expression (i.e., histone deacetylase (HDAC’s)) whereas F. prausnitzii products exerted a weak effects on host transcription.
Although these results have been observed in an ex-vivo model, such as organoids, this model provides an interesting powerful tool to investigate host-microbiome interactions studies at the levels of intestinal epithelial cells.

Lukovac S, Belzer C, Pellis L, Keijser BJ, de Vos WM, Montijn RC, Roeselers G. Differential Modulation by Akkermansia muciniphila and Faecalibacterium prausnitzii of Host Peripheral Lipid Metabolism and Histone Acetylation in Mouse Gut Organoids. MBio. 2014 Aug 12;5(4). pii: e01438-14. doi:10.1128/mBio.01438-14.