Anti-inflammatory effect of lysozyme from hen egg white on mouse peritoneal macrophages

Area of Science:

• Immunology
• Biochemistry

Background:

• Lysozyme, derived from hen egg white, is known for its antimicrobial properties.
• Emerging evidence suggests lysozyme possesses anti-inflammatory effects, but the underlying mechanisms require further elucidation.

Purpose of the Study:

• To investigate the detailed mechanism of the anti-inflammatory effect of hen egg lysozyme.
• To determine if lysozyme affects macrophage phagocytic activity.

Main Methods:

• Utilized mouse macrophage cell line RAW264.7 and primary mouse peritoneal macrophages.
• Stimulated macrophages with lipopolysaccharide (LPS) and treated with lysozyme.
• Assessed cytokine production (TNF-α, IL-6), gene expression, phagocytosis, and JNK phosphorylation.

Main Results:

• Lysozyme significantly suppressed LPS-induced production and gene expression of TNF-α and IL-6.
• Lysozyme treatment did not alter the phagocytic activity of macrophages.
• Lysozyme inhibited the phosphorylation of c-jun N-terminal kinase (JNK) and was rapidly internalized by macrophages.

Conclusions:

• Lysozyme exerts anti-inflammatory effects by intracellularly inhibiting JNK phosphorylation, independent of its effect on phagocytosis.
• These findings elucidate a novel mechanism for lysozyme's anti-inflammatory action in macrophages.