Hyaluronan Fragmentation During Inflammatory Pathologies: A Signal that Empowers Tissue Damage

Area of Science:

• Biochemistry
• Immunology
• Cell Biology

Background:

• Tissue injury response mechanisms are not fully understood.
• Abnormal repair responses contribute to chronic inflammatory diseases with excessive extracellular matrix (ECM) deposition.
• Cell-matrix interactions regulate homeostasis, and ECM integrity modifications promote inflammation.

Purpose of the Study:

• To review the inflammatory actions of small hyaluronic acid (HA) fragments.
• To explore the role of HA fragments in promoting inflammation and ECM degradation.
• To discuss therapeutic strategies targeting HA fragments for inflammatory conditions.

Main Methods:

• Review of recent in vivo reports on the inflammation action of small HA fragments.
• Analysis of evidence on endogenous ECM molecules signaling for ECM degradation and inflammation.
• Examination of how different molecular sizes of HA fragments elicit distinct biological effects.

Main Results:

• Increased deposition of HA is a hallmark of inflammation.
• Small HA fragments exacerbate inflammation by releasing detrimental mediators (ROS, cytokines, chemokines, enzymes) and recruiting leukocytes.
• Highly polymerized HA breaks down into smaller, pro-inflammatory components during inflammatory pathologies.

Conclusions:

• Small HA fragments play a significant role in exacerbating inflammatory responses.
• Targeting specific cell surface receptors for HA fragments presents promising therapeutic avenues.
• Understanding HA fragment modulation is crucial for developing treatments for inflammatory diseases.