Table 3.
Association of QS molecules with gut health.
| QS Molecule | Source | Type of Study | Health Outcomes | Reference |
|---|---|---|---|---|
| 3-oxo-C12:2-HSL | Synthetic | In vitro | Anti-inflammatory effect. | [86] |
| 3-oxo-C12:2 HSL | Human gut microbiota | Cross sectional (analysis of fecal samples of patients with IBDs) | Positive correlation with normobiosis (increased levels of Firmicutes). | [87] |
| In vitro | Anti-inflammatory and positive effect on gut epithelial cell function. | |||
| AI-2 | Mutant E. coli engineered to overproduce AI-2 | Animal study | Increased ratio of Firmicutes to Bacteroidetes in antibiotic-treated mice group. | [88] |
| AI-2 | Lb. rhamnosus GG (LGG) | Animal study | Protective effect of ΔluxS LGG on intestinal cells is significantly lower than effect of wild-type LGG. | [89] |
| AI-2 | Exogenous AI-2 added to milk | Animal study | Dysbiosis was reversed, and inflammation was ameliorated. | [90] |
| DPD (precursor of AI-2) | Exogenous (synthetic) | In vitro (co-culture of WCE of Prevotella. intermedia, Prevotella nigrescens, and estradiol with HMK cells) | DPD modulated the pro-inflammatory effect of estradiol + and inhibited biofilm formation. | [91] |
| AI-2 | Fusobacterium nucleatum | Cross-sectional (analysis of fecal, saliva, and serum samples from patients with CRC and healthy people) | AI-2 levels are higher in CRC samples compared with control samples. | [92] |
| AI-2 | Non-pathogenic E. coli BL21 and W3110 | In vitro (co-culture with HCT-cells) | Increased expression of pro-inflammatory cytokine IL-8 but downregulated after 24 h. | [93] |
IBDs: inflammatory bowel diseases; HMK: human gingival keratinocytes; HCT: human colon cancer; CRC: colorectal cancer; WCE: whole cell extract; DPD: dihydroxy-2,3-pentanedione.