Background: Berberine (BBR) is a plant-based nutraceutical that has been used for millennia to treat diarrheal infections and in contemporary medicine to improve patient lipid profiles. Reduction in lipids, particularly cholesterol, is achieved partly through up-regulation of bile acid synthesis and excretion into the Gastrointestinal tract. The efficacy of BBR is also thought to be dependent on structural and functional alterations of the gut microbiome. However, knowledge of the effects of BBR on gut microbiome communities is currently lacking. Distinguishing indirect effects of BBR on bacteria through altered bile acid profiles is particularly important in understanding how dietary nutraceuticals alter the microbiome.
Results: Germfree mice were colonized with a defined minimal gut bacterial consortium capable of functional bile acid metabolism (Bacteroides vulgatus, Bacteroides uniformis, Parabacteroides distasonis, Bilophila wadsworthia, Clostridium hylemonae, Clostridium hiranonis, Blautia producta; B4PC2). Multi-omics (bile acid metabolomics, 16S rDNA sequencing, cecal metatranscriptomics) were performed in order to provide a simple in vivo model from which to identify network-based correlations between bile acids and bacterial transcripts in the presence and absence of dietary BBR. Significant alterations in network topology and connectedness in function were observed, despite similarity in gut microbial relative abundance between control and BBR treatment. BBR increased cecal bile acid concentrations and altered the taurocholic acid:tauro-β-muricholic acid ratio in the liver. Overall, analysis of correlation networks indicates both bacterial species-specific responses to BBR, as well as functional commonalities among species, such as up-regulation of Na+/H+ antiporter, cell wall synthesis/repair, carbohydrate metabolism and amino acid metabolism. Bile acid concentrations in the gastrointestinal (GI) tract increased significantly during berberine treatment and developed extensive correlation networks with expressed genes in the B4PC2 community.
Conclusions: This work has important implications for interpreting the effects of berberine on structure and function of the complex gut microbiome, which may lead to targeted pharmaceutical interventions aimed to achieve the positive physiological effects previously observed with berberine supplementation.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8
This is a list of supplementary files associated with this preprint. Click to download.
Loading...
On 23 Oct, 2020
On 20 Oct, 2020
On 19 Oct, 2020
On 19 Oct, 2020
On 14 Oct, 2020
On 08 Sep, 2020
On 07 Sep, 2020
On 07 Sep, 2020
Posted 22 Jun, 2020
Received 31 Aug, 2020
On 31 Aug, 2020
On 06 Aug, 2020
Received 27 Jul, 2020
Received 24 Jul, 2020
On 08 Jul, 2020
On 28 Jun, 2020
Invitations sent on 22 Jun, 2020
On 19 Jun, 2020
On 18 Jun, 2020
On 18 Jun, 2020
On 23 Oct, 2020
On 20 Oct, 2020
On 19 Oct, 2020
On 19 Oct, 2020
On 14 Oct, 2020
On 08 Sep, 2020
On 07 Sep, 2020
On 07 Sep, 2020
Posted 22 Jun, 2020
Received 31 Aug, 2020
On 31 Aug, 2020
On 06 Aug, 2020
Received 27 Jul, 2020
Received 24 Jul, 2020
On 08 Jul, 2020
On 28 Jun, 2020
Invitations sent on 22 Jun, 2020
On 19 Jun, 2020
On 18 Jun, 2020
On 18 Jun, 2020
Background: Berberine (BBR) is a plant-based nutraceutical that has been used for millennia to treat diarrheal infections and in contemporary medicine to improve patient lipid profiles. Reduction in lipids, particularly cholesterol, is achieved partly through up-regulation of bile acid synthesis and excretion into the Gastrointestinal tract. The efficacy of BBR is also thought to be dependent on structural and functional alterations of the gut microbiome. However, knowledge of the effects of BBR on gut microbiome communities is currently lacking. Distinguishing indirect effects of BBR on bacteria through altered bile acid profiles is particularly important in understanding how dietary nutraceuticals alter the microbiome.
Results: Germfree mice were colonized with a defined minimal gut bacterial consortium capable of functional bile acid metabolism (Bacteroides vulgatus, Bacteroides uniformis, Parabacteroides distasonis, Bilophila wadsworthia, Clostridium hylemonae, Clostridium hiranonis, Blautia producta; B4PC2). Multi-omics (bile acid metabolomics, 16S rDNA sequencing, cecal metatranscriptomics) were performed in order to provide a simple in vivo model from which to identify network-based correlations between bile acids and bacterial transcripts in the presence and absence of dietary BBR. Significant alterations in network topology and connectedness in function were observed, despite similarity in gut microbial relative abundance between control and BBR treatment. BBR increased cecal bile acid concentrations and altered the taurocholic acid:tauro-β-muricholic acid ratio in the liver. Overall, analysis of correlation networks indicates both bacterial species-specific responses to BBR, as well as functional commonalities among species, such as up-regulation of Na+/H+ antiporter, cell wall synthesis/repair, carbohydrate metabolism and amino acid metabolism. Bile acid concentrations in the gastrointestinal (GI) tract increased significantly during berberine treatment and developed extensive correlation networks with expressed genes in the B4PC2 community.
Conclusions: This work has important implications for interpreting the effects of berberine on structure and function of the complex gut microbiome, which may lead to targeted pharmaceutical interventions aimed to achieve the positive physiological effects previously observed with berberine supplementation.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8
This is a list of supplementary files associated with this preprint. Click to download.
Loading...