Kaempferol-3-O-rutinoside protects myocardial cell injury by inhibiting the TXNIP/NLRP3 pathway

Abstract

Kaempferol-3-O-rutinoside (KR), a compound commonly found in green tea, has demonstrated significant myocardial protective effects. The aim of this study was to reveal the cardioprotective mechanism of KR. In this study, molecular docking was employed to predict the binding affinity of KR to thioredoxin-interacting protein (TXNIP). An injury model of H9c2 cells was established using lipopolysaccharide (LPS) and adenosine triphosphate (ATP). Lactate dehydrogenase (LDH) levels were measured using specific kits, while total superoxide dismutase (T-SOD), malondialdehyde (MDA), glutathione (GSH), and catalase (CAT) activities were assessed with colorimetric assays. The reactive oxygen species (ROS) level was determined using the DCFH-DA fluorescent probe assay. In addition, the expression levels of TXNIP, NLR-family pyrin domain-containing protein 3 (NLRP3), cysteinyl aspartate specific proteinase-1 (Caspase-1), and thioredoxin (TRX) were quantified by reverse transcription polymerase chain reaction (RT-PCR) and Western blot (WB) assays. Levels of interleukin-1β (IL-1β) and IL-18 were determined by ELISA. The results indicated that KR has a specific binding affinity for TXNIP. KR was found to reduce LDH and MDA activities, increase CAT, GSH, T-SOD, and inhibit ROS production. Mechanistically, KR decreased the gene and protein expressions of TXNIP, Caspase-1, and NLRP3, while increasing the gene and protein expression of TRX. Also, KR decreased the levels of IL-1β and IL-18. In conclusion, the protective mechanism of KR against cardiomyocyte injury involves the inhibition of the TXNIP/NLRP3 pathway, providing experimental evidence for its potential clinical application.