Hydroxysafflor Yellow A Inhibits TNF-α-Induced Inflammation of Human Fetal Lung Fibroblasts via NF-κB Signaling Pathway

الملخص EN

Objective.

Hydroxysafflor yellow A (HSYA), an effective ingredient of the Chinese herb Carthamus tinctorius L, attenuated bleomycin-induced pulmonary fibrosis in mice.

This study is to investigate the effect of HSYA on the proliferation and inflammatory level of human fetal lung fibroblasts (MRC-5 cells) induced by tumor necrosis factor-α (TNF-α) and explore the underlying mechanisms.

Methods.

MRC-5 cells were treated with different concentrations of TNF-α, HSYA, or/and etanercept (ENCP, TNF-α receptor (TNFR1) antagonist, 500 ng/mL) before cell proliferation was detected.

The laser confocal microscope was used to observe the role of HSYA in binding of TNF-α and its receptor.

Co-immunoprecipitation was used to detect the binding of TNFR1 and TAK1-TAB2 complex.

Real-time quantitative RT-PCR and western blot were used to detect the expressions of inflammation-related cytokines and proteins related with the NF-κB pathway.

Luciferase reporter gene assay and chromatin coprecipitation method were used to detect the interaction between AP-1 and TGF-β1 promoter.

Results.

TNF-α (5 ng/mL) was used to induce inflammation and proliferation in MRC-5 cells.

HSYA can partially suppress the stimulation of TNF-α on proliferation and inflammatory response of MRC-5 cells.

HSYA could compete with TNF-α to bind with TNFR1 and hamper the binding of TNFR1 to TAK1-TAB2 complex.

In addition, HSYA could also inhibit the activation of the NF-κB signal pathway and suppress the binding of TGF-β1 promoter with AP-1.

Conclusion.

Evidence in this study suggested that HSYA affects TNF-α-induced proliferation and inflammatory response of MRC-5 cells through the NF-κB/AP-1 signaling pathway, which may provide theoretical basis for HSYA treatment in pulmonary fibrosis.