Unlocking Toll-Like Receptors: Targeting Therapeutics for Respiratory Tract Infections and Inflammatory Disorders

Area of Science:

• Immunology
• Pharmacology
• Pathophysiology

Background:

• Toll-like Receptors (TLRs) are crucial for innate immunity, recognizing pathogens and activating inflammatory responses via cytokines and interleukins.
• TLRs are implicated in COVID-19 pathophysiology, mediating excessive inflammation that worsens disease severity and influences both acute and long-term outcomes.
• Increased inflammatory conditions like atherosclerosis and viral myocarditis are linked to COVID-19, with evidence suggesting TLR-mediated pro-inflammatory signaling plays a role.

Purpose of the Study:

• To elucidate the role of TLRs in inflammatory diseases associated with COVID-19, including viral myocarditis, acute lung infections, and atherosclerosis.
• To review herbal drugs and their mechanisms of action on TLRs and associated signaling pathways.
• To highlight the need for clearer understanding of TLRs' contribution to COVID-19 and evidence for herbal interventions.

Main Methods:

• Literature review focusing on Toll-like Receptors (TLRs) and their involvement in COVID-19 related inflammatory conditions.
• Analysis of mechanisms of action for herbal drugs including *Platycodon grandiflorum*, *Acanthopanax senticosus*, *Scutellaria baicalensis Georgi*, and *Engelhardia roxburghiana*.
• Examination of TLR signaling pathways such as NF-κB, MyD88-dependent and independent pathways, and Plasmacytoid Dendritic Cells (DCs).

Main Results:

• TLRs are critically involved in the pathophysiology of COVID-19, exacerbating inflammation and disease severity.
• Evidence suggests TLRs mediate pro-inflammatory signaling in conditions like viral myocarditis, acute lung infections, and atherosclerosis.
• Several herbal drugs demonstrate potential mechanisms for modulating TLR activity and associated inflammatory pathways.

Conclusions:

• TLRs play a significant role in the inflammatory response during COVID-19 and related comorbidities.
• Herbal interventions targeting TLRs offer potential therapeutic strategies for managing COVID-19 associated inflammation.
• Further research is needed to clarify TLRs' specific roles and validate herbal treatments for clinical application.