Effects of bufei yishen formula on klotho gene expression and inflammation-related rig-i/nf-κb pathway in cigarette smoke extract-treated beas-2b cells

Abstract

Purpose: To investigate the anti-inflammatory effect of Bufei yishen formula on chronic obstructive pulmonary disease (COPD) and klotho expression in cigarette smoke extract (CSE)-treated BEAS-2B cells. Methods: Cigarette smoke extract (CSE) was diluted in Dulbecco’s modified Eagle’s medium (DMEM) and used to treat a COPD cell model established using BEAS-2B cells. The CSE-treated cells were transfected with klotho overexpression plasmid, and the COPD cell model was treated with Bufei yishen formula. Dexamethasone was used as positive control. Changes in the expressions of klotho, RIG-I, and NF-ĸB were determined using reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, while enzyme linked immunosorbent assay (ELISA) was used to evaluate changes in the expressions of IL-6 and TNF-α. Results: Klotho expression level was reduced in COPD model. Overexpression of klotho inhibited the expressions of IL-6, TNF-α, RIG-I, NF-κB, but bufei yishen formula increased klotho expression level and decreased the expressions of RIG-I, NF-κB, IL-6 and TNF-α. However, after CSE treatment, the anti-inflammatory effect of the formula decreased significantly when klotho expression was knocked down. Conclusion: Bufei yishen formula possesses anti-inflammatory effects which are significantly decreased after klotho knockdown. This suggests that the formula probably acts by upregulating klotho expression, thereby down-regulating the expressions of IL-6 and TNF-α via RIG-I/NF-κB pathway.