Epigallocatechin-3-gallate ameliorates lipopolysaccharide-induced acute lung injury by suppression of TLR4/NF-κB signaling activation.
Level 5 - mechanism / opinion, no new human data
Preclinical animal model without human clinical data
PubMed 31241712 · doi:10.1590/1414-431X20198092
What was done
Male BALB/c mice were treated with epigallocatechin-3-gallate (EGCG, 10 mg/kg intraperitoneally) 1 hour prior to lipopolysaccharide administration (LPS, 10 mg/kg intraperitoneally) to evaluate protective effects against acute lung injury. Researchers measured blood gas changes, lung histological lesions, wet-to-dry weight ratios, myeloperoxidase (MPO) activity, inflammatory cytokines (TNF-α, IL-1β, IL-6) across lung tissue, serum, and bronchoalveolar lavage fluid, and expression levels of TLR4/NF-κB pathway proteins (TLR-4, MyD88, TRIF, p-p65, p65, and IκB-α).
What was found
The abstract does not provide exact numerical values or effect sizes. Pretreatment with EGCG decreased blood gas abnormalities, histological lesions, wet-to-dry ratios, and MPO activity following LPS challenge. EGCG significantly decreased TNF-α, IL-1β, and IL-6 concentrations in lung, serum, and bronchoalveolar lavage fluid. It also reduced lung expression of TLR-4, MyD88, TRIF, and p-p65 while increasing IκB-α expression, without altering total p65 levels.
Why it matters
This study provides preclinical mechanistic evidence that EGCG downregulates TLR4-mediated NF-κB inflammatory signaling in endotoxin-induced lung injury.
Limits
The study is restricted to an in vivo mouse model and cannot be directly translated to human clinical sepsis or acute lung injury. Total animal sample sizes and quantitative effect sizes are omitted from the abstract. In addition, EGCG was administered prophylactically before LPS exposure rather than therapeutically after injury onset.
Cited by
- supports EGCG (epigallocatechin gallate) is an effective inhibitor of LPS-induced inflammatory stimulation.