Dietary Silk Peptide Inhibits LPS-Induced Inflammatory Responses by Modulating Toll-Like Receptor 4 (TLR4) Signaling

Area of Science:

• Immunology
• Biochemistry
• Materials Science

Background:

• Acid-hydrolyzed silk peptide (SP) has traditional uses in medicine, but its anti-inflammatory mechanisms are unclear.
• Toll-like receptor 4 (TLR4) is crucial for innate immunity, responding to pathogens and molecules like lipopolysaccharide (LPS).

Purpose of the Study:

• To elucidate the mechanism by which silk peptide (SP) modulates inflammatory responses.
• To investigate the role of SP in regulating the toll-like receptor 4 (TLR4) signaling pathway.

Main Methods:

• Utilized macrophages (RAW264.7 cells and bone marrow-derived macrophages) to study TLR4 signaling.
• Administered LPS to C57BL/6 mice and analyzed lymph node, spleen, and serum samples.
• Assessed nitric oxide and reactive oxygen species production in LPS-induced cellular models.

Main Results:

• Silk peptide (SP) demonstrated anti-inflammatory effects in vivo, as evidenced by analysis of mouse tissues and serum.
• SP was shown to inhibit LPS-induced nitric oxide and reactive oxygen species production in macrophage cell lines.
• SP modulates immune responses through the TLR4 signaling pathway.

Conclusions:

• Acid-hydrolyzed silk peptide (SP) effectively inhibits lipopolysaccharide (LPS)-induced inflammatory responses.
• The anti-inflammatory action of SP is mediated by the modulation of the TLR4 signaling pathway.