Mechanism of Modified Erchentang on Signaling Pathway of TLR4/MyD88/NF-κB in Lung Tissue of Rats with Chronic Obstructive Pulmonary Disease / 中国实验方剂学杂志

ABSTRACT

Objective: To study the effect of modified Erchentang on expressions of Toll-like receptor 4 (TLR4), myeloid differentiation factor (MyD88) and nuclear factor-κB (NF-κB) genes in the lung tissue homogenate of rats with chronic obstructive pulmonary disease (COPD). Method: Forty SD rats were randomly divided into normal group, model group, modified Erchentang group and EVP4593 (NF-κB inhibitor) group. Rat COPD models were prepared through cigarette smoke and tracheal dripping with lipopolysaccharide (LPS). After the modeling, normal and model groups were intragastrically given normal saline solution, EVP4593 group was given EVP4593(1 mg · kg-1) through subcutaneous injection, and modified Erchentang group was given corresponding herbal drugs intragastrically (10 g · kg-1) for 14 days. The levels of high mobility group box 1(HMGB1), chemokines CXCL-2, CXCL-3 and monocyte chemoattractant protein-1 (MCP-1) in rats serum were detected by enzyme-linked immunosorbent assay in rats serum. The expressions of Toll-like receptors 4(TLR4), myeloid differentiation factor (MyD88) and nuclear factor-κB p65 (NF-κB p65) mRNA were detected by Real-time fluorescence quantitative PCR (Real-time PCR) method. Western blot were used to detect the levels of TLR4, MyD88, NF-κB p65 and p-NF-κB p65 protein. Immunohistochemistry (IHC) method was used to detect the localization and expressions of TLR4, MyD88 and p-NF-κB p65 protein in the lung tissue. Result: The mRNA and protein expressions of TLR4, MyD88 and NF-κB p65 were increased significantly (PPκB p65 mRNA and protein were decreased significantly (PConclusion: Modified Erchentang may inhibit the inflammatory response of COPD effectively. The mechanism may be related to the inhibition of the expressions of the signal molecule genes involved in the TLR4/MyD88/NF-κB pathway and the reduction of the release of HMGB1, CXCL-2, CXCL-3 and MCP-1.