Brazilin inhibits the inflammatory immune response induced by LPS in THP-1 cells

Abstract

Abstract Objective To investigate the inhibitory effect of Brazilin (BN) on the inflammatory response of THP-1-derived macrophages induced by LPS. Methods THP-1 cells were induced with PMA to extend pseudopodia and form macrophages, and the inflammatory model was induced by LPS. The cell survival rate intervented by Brazilin was determined by the CCK-8 method, and the expression of PD-1 was detected by Flow cytometry, and contents of the cytokines IL-10 and TNF-α in the extracted supernatant of THP-1 cells were detected by ELISA, and the mRNA level was detected by RT‒PCR, while the protein level were detected by Western blot. Results The results showed that the best concentration of Brazilin was 12 µg/mL. The best concentration of simvastatin was 15 µg/mL, and the growth was concentration dependent. The expression of PD-1 on the cell surface in the two groups was significantly decreased compared with the control group, and the differences in the Brazilin group and the simvastatin group were significant (P < 0.01; P < 0.001; P < 0.001). The concentrations of TNF-α in the drug groups were significantly decreased while the IL-10 concentration was increased, and compared with the model group, the two drug groups were highly statistically significant (P < 0.001). The mRNA and the protein expression levels of PD-1, NF-κB, TLR4 and MMP-9 in the test groups had extremely significant difference compared with the model group (P < 0.001). Conclusion Brazilin can inhibit the abnormal activation of PD-1, TLR4, NF-κB and MMP-9 and is a good anti-AS drug that can not only reduce blood lipids but also have immunoregulatory and anti-inflammatory activity, laying a solid theoretical foundation for future screening and development of anti-AS drugs.