Table 2.
Overview of gut bacterial taxa currently described to impact gastrointestinal motility, and experimental models used for motility assessment
| Gut bacterial species | Effect on gut motility | Methods used | Model organism and effect size (N) | Reference |
|---|---|---|---|---|
|
-Lactobacillus acidophilus -Bifidobacterium bifidum |
-Administration of L. acidophilus and B. bifidum to germ-free rats displayed improved intestinal transit and contractility of the small intestine | -Myoelectric recording in vivo -Measurements of a radioactive marker (Na251CrO4) distribution along the small intestine |
Rats (N = 5-18) | 35 |
| -Bacteroides thetaiotamicron | -Critical for enteric nervous system innervation -Administration of B. thetaiotamicron (Bt) restored the expression of excitatory and inhibitory motor neurons signaling enzymes |
-Colonic manometry in vitro (colonic motility measurements in the colonic tissue of SPF, GF and Bt-conventionalized mice) -Immunohistochemistry (neuronal cell populations determination) -qPCR (expression of ENS signaling enzymes) |
Mice (N = 3-5) | 42 |
| -Vibrio cholerae | -Use of the syringe-like type VI secretion system for induction of intestinal movements, which leads to expulsion of the resident microbiota by the host | -In vivo imaging of fluorescently-labeled bacterial populations and dynamics of unlabeled intestinal tissue (motility) | Zebrafish (N = 5-6) | 48 |
| -Lactobacillus rhamnosus GG | -Increase of choline acetyltransferase expression (responsible for synthesis of main metabolite involved in gut motility, acetylcholine) in the ENS after administration of L. rhamnosus GG | -RT-PCR -Immunoblotting -Immunostaining |
Mice (N = 3-5) | 43 |
| -Escherichia coli Nissle 1917 | -Inhibitory effect on the smooth muscle contractility | -Ex vivo organ bath model (contractility measurements after application of E. coli Nissle 1917 bacterial supernatant) | Rats (N = 5) | 59 |
|
-Bifidobacterium longum -Lactobacillus acidophilus -Streptococcus thermophilus -Enterococcus faecalis |
Inhibitory effect on human colonic smooth muscle in vitro | -Ex vivo organ bath model (contractility measurements after application of sonicated cell fractions and bacterial supernatants) | Humans (N = 25) | 58 |
|
Akkermansia muciniphila Bacteroides spp -Alistipes |
Modulation of longer gut transit time in humans | -Blue dye method (measurements of gut transit time in humans) | Humans (N = 863) | 134 |
|
-Ruminococcus -Bacteroides -Prevotella |
-Abundance of Ruminococcus and Bacteroides is linked to shorter transit times -Abundance of Prevotella is linked to longer transit times |
-Bristol Stool Scale score (measurements of colonic transit times in humans) | Humans (N = 53) | 135 |
| -Lactic acid bacteria (Lactobacillus plantarum 2362, Lactobacillus casei ssp. paracasei 19, Leuconostoc raffinolactis 23~77:1, and Pediococcus pentosaceus 16:1) | -Amelioration of the small intestinal contractile impairment in traumatic brain injury mouse model fed with probiotic mixture | -Ex vivo organ bath model (contractility measurements) | Mice (N = 6) | 65 |
| -Clostridium butyricum | -Promotion of ICCs proliferation and intestinal motility by the regulation of TLR2 expression on ICCs after stimulation with C. butyricum suspensions | -Cell culture (culture of ICCs) RT-PCR (expression of TLR2) -Western Blot (protein levels of TLR2) |
NA | 66 |
| -Bifidobacterium -Lactobacillus | -Modulation of ghrelin signaling (acetate, propionate and butyrate) | -Cell culture (activation of G protein coupled receptors using β-arrestin assay stimulated with bacterial supernatants) | NA | 71 |
| -Spore-forming bacteria | -Modulation of metabolites that promote transit time | -GI transit assay using carmine red in vivo (gut motility measurements after colonization of germ-free mice with fecal samples from spore-forming conventionalized mice) | Mice (N = 4-8) | 90 |
| -Lactobacillus casei subsp. casei | -Administration of heat killed L. casei subsp. casei increases levels of 5-HT in the colonic tissue and lowers bead expulsion time | -HPLC (5-HT levels) Bead expulsion test (colonic transit analysis) |
Mice (N = 6) | 91 |
| -Escherichia coli -Fusobacterium nucleatum | -Modulation of gut motility via L-type voltage-dependent Ca2+ channels located on the colonic smooth muscle cells -Control of serotonin release from model of enterochromaffin cells |
-RIN14B cell line in vitro (5-HT release measurements after application of 5-hydroxyindole produced from E. coli and F. nucleatum derived)) -GI transit assay using carmine red in vivo (gut motility measurements after application of 5-hydroxyindole produced from E. coli and F. nucleatum derived) -Ex vivo organ bath model (colonic contractility measurements after application of 5-hydroxyindole produced from E. coli and F. nucleatum derived-) |
Rats (N = 6-10) | 4 |
| -Akkermansia muciniphila | -Production of protein P9 signals to L cells to produce GLP-1 | -ELISA (GLP-1 quantification after stimulation with bacterial pellets or supernatants) | NA | 72 |
| -Edwardsiella tarda | -Activation of TRPA1 in EECs, leads to production of 5-HT from enterochromaffin cells and thus modulate gut motility | -Real-time measurements of EECs in vivo in zebrafish (activation of TRPA1 and gut motility after oral gavage of indole or indole-3-acetaldehyde produced from E. tarda to zebrafish) -Amperometry (5-HT release after application of indole or indole-3-acetaldehyde produced from E. tarda to the mouse or human small intestinal tissue) |
Zebrafish (N = 117-213) | 102 |
| -Fusobacteria | -Improvement of the symptoms of constipation in rat loperamide-induced constipation model | -Charcoal propulsion test (gut motility measurements after oral administration of quercetin derived from Fusobacteria genera to rats) | Rats (N = 3) | 103 |
|
-Prevotella -Lactobacillus -Alistipes |
-Enhancement of colonic contractility ex vivo and stool frequency in vivo |
-Ex vivo organ bath model (colonic contractility measurements after application of saturated long-chain fatty acids derived from Prevotella, Lactobacillus and Alistipes genera to the rat colonic tissue) -Fecal pellets collection (stool frequency measurements after conventionalization of germ-free rats) |
Rats (N = 6-8) | 104 |
| -Lactobacillus fermentum | -Acceleration of gastrointestinal transit and gastric emptying | -Charcoal propulsion test (gut transit measurements after oral administration of ferulic acid derived from L. fermentum to rats) -Phenol red detection (gastric emptying measurements after oral administration of ferulic acid derived from L. fermentum to rats) |
Rats (N = 8) | 106 |
| -Morganella morganii -Lactobacillus reuteri | -Promotion of colonic motility via activation of histamine receptors in the gut | -Fecal output assay (after individual mice were fed with L-histamine) | Mice (N = 3-5) | 107 |
| -Clostridium sporogenes | -Potent stimulation of ileal motility ex vivo | -Ex vivo organ bath model (ileal contractility measurements after application of 3-(3,4-dihydroxyphenyl)propionic acid derived from C. sporogenes to the ileal rat tissue) | Mice (N = 4-6) | 108 |