Tryptophol Acetate and Tyrosol Acetate, Small-Molecule Metabolites Identified in a Probiotic Mixture, Inhibit...

Area of Science:

• Microbiology
• Immunology
• Biochemistry

Background:

• Probiotic fermented foods are thought to benefit health, but robust evidence for systemic therapeutic effects is limited.
• Hyperinflammation, or cytokine storm, is a dangerous overreaction of the immune system with high mortality.
• Kluyveromyces marxianus is a probiotic yeast used in fermented foods.

Purpose of the Study:

• To investigate the anti-inflammatory effects of specific metabolites produced by Kluyveromyces marxianus.
• To determine if tryptophol acetate and tyrosol acetate can mitigate hyperinflammation.
• To elucidate the molecular mechanisms underlying the anti-inflammatory actions of these metabolites.

Main Methods:

• In vitro and in vivo studies using lipopolysaccharide (LPS)-induced hyperinflammation models in mice.
• Analysis of cytokine levels (IL-6, IL-1α, IL-1β, TNF-α), reactive oxygen species, and phagocytosis.
• Assessment of molecular pathways including TLR4, IL-1R, TNFR, and NF-kB signaling, as well as A20 expression.

Main Results:

• Tryptophol acetate and tyrosol acetate, when administered together, significantly reduced hyperinflammation markers in mice.
• Pro-inflammatory cytokine levels were attenuated to baseline, preserving essential immune functions like phagocytosis.
• The anti-inflammatory effects were linked to the downregulation of TLR4, IL-1R, and TNFR pathways and NF-kB inhibition via increased A20.

Conclusions:

• Tryptophol acetate and tyrosol acetate are key anti-inflammatory metabolites from Kluyveromyces marxianus.
• These molecules effectively inhibit hyperinflammation without compromising crucial immune responses.
• The findings highlight potential therapeutic applications of these small molecules for managing severe inflammatory conditions.